To see the other types of publications on this topic, follow the link: Nucleic acid-binding protein 2.
Dissertations / Theses on the topic 'Nucleic acid-binding protein 2'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Nucleic acid-binding protein 2.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Porter, Jason Robert. "SPLIT-PROTEIN REASSEMBLY METHODS FOR THE DETECTION AND INTERROGATION OF BIOMOLECULAR INTERACTIONS AND MODULATORS THEREOF." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194359.
Full textAbstract:
The interactions between protein-protein, protein-nucleic acid, and protein-small molecules are central to biological processes and are key for the design of new therapeutics. Rapid and easy to implement methodologies are needed that enable the interrogation of these interactions in a complex cellular context. Towards this goal, I have utilized the concept of split-protein reassembly, also called protein complementation, for the creation of a variety of sensor architectures that enable the interrogation of protein-nucleic acid, protein-protein, and protein-small molecule interactions. Utilizing the enzymatic split-reporter β-lactamase and existing zinc finger design strategies we applied our recently developed technology termed SEquence-Enabled Reassembly (SEER) towards the creation of a sensor capable of the specific detection of the CryIA transgene. Additionally, the split β-lactamase reporter was utilized for the sitespecific determination of DNA methylation at cytosine residues that is involved in epigenetic regulation. This method, dubbed mCpG-SEER, enabled the direct detection of femtomole levels of dsDNA methylation in sequence specific manner. In a separate endeavor, we have developed and optimized the first cell-free split-reporter systems for GFP, split β-lactamase, and firefly luciferase for the successful dsDNA-dependent reassembly of the various reporters. Our cell free in vitro translation systems eliminates previous bottlenecks encountered in split-reporter technologies such as laborious transfection/cell culture or protein purification. Capitalizing on the ease of use and speed afforded by this new technology we describe the sensitive detection of protein-protein, protein-nucleic acid, and protein-small molecule interactions and inhibitors thereof. In a related area, we have applied this rapid cell-free split-firefly luciferase assay to the specific interrogation of a large class of helix-receptor protein-protein interactions. We have built a panel consisting of the clinically relevant Bcl-2 family of proteins, hDM2, hDM4, and p53 and interrogated the specificity of helix-receptor interactions as well as the specificity of peptide and small-molecule inhibitors of these interactions. Finally, we describe the further applications of our cell-free technology to the development of a large number of general split-firefly luciferase sensors for the detection of ssRNA sequences, the detection of native proteins, the evaluation of protease activity, and interrogation of enzyme-inhibitor interactions. The new methodologies provided in this study provides a general and enabling methodology for the rapid interrogation of a wide variety of biomolecular interactions and their antagonists without the limitations imposed by current in vitro and in vivo approaches.
2
Ashton, Nicholas W. "Characterisation of human single-stranded DNA-binding protein 1 (hSSB1) regulation by post-translational modifications." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/98660/1/Nicholas_Ashton_Thesis.pdf.
Full textAbstract:
Human single-stranded DNA-binding protein 1 (hSSB1) is required for the timely repair of double-strand DNA breaks, as well as the stabilisation and restart of stalled replication forks. In this work, evidence is provided that cellular survival in response to replication stress is promoted by dynamic phosphorylation of hSSB1 by the DNA-dependent protein kinase (DNA-PK) and PPP-family protein phosphatases. These data provide insight into the functional regulation of hSSB1 following replication fork disruption.
3
Webb, Robin. "THE CELLULAR NUCLEIC ACID BINDING PROTEIN IN AGING AND DISEASE." UKnowledge, 2013. http://uknowledge.uky.edu/biochem_etds/7.
Full textAbstract:
The ZNF9 gene on chromosome 3 encodes the cellular nucleic acid binding protein (CNBP), a ubiquitously expressed, 177 amino acid (≈19.5kDa) protein that is highly conserved among vertebrates. The function of the protein is largely unknown, however an expansion in the first intron of the protein results in myotonic dystrophy type 2 (DM2), a multisystemic disease featuring cardiac arrhythmia, muscle wasting, cataracts, and a range of neuropathologies. Remarkably, we recently discovered that CNBP is involved in regulating the activity of β-secretase, the enzyme that produces the first cleavage event in the generation of the amyloid-β peptide (Aβ). The progressive fibrillization and deposition of Aβ is widely believed to be the primary causal factor in the development of Alzheimer’s disease (AD), and AD-like pathology in individuals with Down syndrome (DS). DS provides a unique model for evaluating how these factors change in the aged brain as compared to young brain, and how such changes affect the proportion of DS patients with AD. In the AD brain, both BACE1 and BACE2 increased from an early stage of disease; in DS brains, BACE1 significantly decreased (p<0.04) with age, whereas BACE2 was unchanged, even though the gene for BACE2 is located within the DS obligate region of chromosome 21. BACE1 and BACE2 activity levels were highly correlated in this series (r2 = 0.95), indicating that there may be a higher degree of shared regulation than previously believed. This implicates regulators of BACE as potentially critical for the development of AD, and our data suggests that CNBP may be one such regulator. In AD, CNBP increases early in the disease process, a change that does not occur in the normal aging process or in DS. CNBP and BACE protein levels were correlated in these cases (p<0.001), while there was no relationship between CNBP and age, or CNBP and Aβ, in either the human or mouse brain, indicating that CNBP does not increase as a consequence of normal aging. Thirty day overexpression of CNBP following adeno-associated viral delivery in murine gastrocnemius muscle resulted in an increase in BACE1 protein (p<0.01) and a consequential increase in Aβ production (p<0.01). Other experiments indicated that CNBP overexpression did not affect the half-life of BACE1 mRNA or protein, but resulted in an increase in BACE1 translation. These data indicate that CNBP is an important regulator of β-secretase, and may play an important role in the onset and progression of AD.
4
Cirillo, Davide. "Prediction of protein and nucleic acid interactions." Doctoral thesis, Universitat Pompeu Fabra, 2016. http://hdl.handle.net/10803/403537.
Full textAbstract:
The purpose of my doctoral studies has been the development of bioinformatics methods to quantitatively evaluate associations between proteins and nucleic acids (NAs). This thesis aims at providing insights into molecular features and still relatively unknown mechanisms of protein-NAs associations, such as RNA-binding proteins and long noncoding RNAs as well as transcription factors and regulatory DNA elements. In this work, I present two algorithms, catRAPID omics express and PAnDA, for the prediction of RNA- and DNA-protein interaction respectively. Those computational methods offer the possibility to address experimental problems and guide new approaches largely facilitating experimental design and procedures<br>Mis estudios de doctorado han tenido como propósito principal el desarrollo de herramientas bioinformáticas para la evaluación de interacciones entre proteínas y ácidos nucleicos (ANs) de forma cuantitativa. Por consiguiente, esta tesis apunta a proporcionar conocimientos sobre características moleculares y mecanismos de asociación proteína-AN aún relativamente desconocidos; concretamente, la asociación de proteínas a ARNs y ARNs no codificantes, a la vez que factores de transcripción y elementos de regulación del ADN. En este proyecto presento dos algoritmos: catRAPIDomics express y PAnDA, cuyas finalidades son las de predecir interacciones proteína-ARN y proteína-ADN respectivamente. Dichos métodos computacionales ofrecen la posibilidad de abordar problemas experimentales, así como de guiar el diseño y procedimiento de nuevas estrategias para su resolución.
5
Weber, Janine. "Molecular characterization of the neuronal nucleic acid-binding protein Pur-α". Diss., Ludwig-Maximilians-Universität München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-184483.
Full text
6
Holler, Christopher J. "THE CELLULAR NUCLEIC ACID BINDING PROTEIN REGULATES THE ALZHEIMER’S DISEASE β-SECRETASE PROTEIN BACE1". UKnowledge, 2012. http://uknowledge.uky.edu/biochem_etds/12.
Full textAbstract:
Alzheimer’s disease (AD) is the most common neurodegenerative disease affecting the elderly population and is believed to be caused by the overproduction and accumulation of the toxic amyloid beta (Aβ) peptide in the brain. Aβ is produced by two separate enzymatic cleavage events of the larger membrane bound amyloid precursor protein, APP. The first, and rate-limiting, cleavage event is made by beta-secretase, or BACE1, and is thus an attractive therapeutic target. Our lab, as well as many others, has shown that BACE1 protein and activity are increased in late-stage sporadic AD. We have extended these findings to show that BACE1 is increased in the earliest stages of AD before the onset of significant Aβ accumulation, indicating a potential causal role in the disease. Interestingly, BACE1 mRNA levels are unchanged in AD, leading to reason that a post-transcriptional method of BACE1 regulation is altered in disease. To date, the mechanism for this aberrant post-transcriptional regulation has not been elucidated. This study has implicated the cellular nucleic acid binding protein (CNBP), a highly conserved RNA binding protein, as a positive regulator of BACE1 translation, with implications for the etiology of sporadic AD. CNBP overexpression in cultured cells or spiked into a cell-free in vitro translation system increased BACE1 protein expression without affecting BACE1 mRNA levels. Knockdown of CNBP reduced BACE1 protein and mRNA slightly. Furthermore, CNBP associated with BACE1 mRNA in cell lysates and bound directly to the BACE1 5’ UTR in vitro, which confers most of the regulatory activity. Importantly, CNBP was increased in the progression of AD and correlated with BACE1 expression. Cellular stressors (such as glucose deprivation and oxidative stress) that occur in the AD brain increase BACE1 translation and we have found that these stressors increased CNBP expression as well. Early experimental evidence suggests that CNBP may enhance BACE1 translation through a cap-independent mechanism, which is an alternative translational pathway activated by cell stress. These studies indicate that the RNA binding protein CNBP is a novel trans-acting factor important for the regulation of BACE1 protein production and may be a viable therapeutic target for AD.
7
Prikryl, Jana 1976. "Functions of organelle-specific nucleic acid binding protein families in chloroplast gene expression." Thesis, University of Oregon, 2009. http://hdl.handle.net/1794/10614.
Full textAbstract:
xii, 83 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.<br>My dissertation research has centered on understanding how nuclear encoded proteins affect chloroplast gene expression in higher plants. I investigated the functions of three proteins that belong to families whose members function solely or primarily in mitochondrial and chloroplast gene expression; the Whirly family (ZmWHY1) and the pentatricopeptide repeat (PPR) family (ZmPPR5 and ZmPPR10). The Whirly family is a plant specific protein family whose members have been described as nuclear DNA-binding proteins involved in transcription and telomere maintenance. I have shown that ZmWHY1 is localized to the chloroplast where it binds nonspecifically to DNA and also binds specifically to the atpF group II intron RNA. Why1 mutants show reduced atpF intron splicing suggesting that WHY1 is directly involved in atpF RNA maturation. Why1 mutants also have aberrant 23S rRNA metabolism resulting in a lack of plastid ribosomes. The PPR protein family is found in all eukaryotes but is greatly expanded in land plants. Most PPR proteins are predicted to localize to the mitochondria or chloroplasts where they are involved in many RNA-related processes including splicing, cleavage, editing, stabilization and translational control. Our results with PPR5 and PPR10 suggest that most of these activities may result directly from the unusually long RNA binding surface predicted for PPR proteins, which we have shown imparts two biochemical properties: site-specific protection of RNA from other proteins and site-specific RNA unfolding activity. I narrowed down the binding site for PPR5 and PPR10 to ∼45 nt and 19 nt, respectively. I showed that PPR5 contributes to the splicing of its group II intron ligand by restructuring sequences that are important for splicing. I used in vitro assays with purified PPR10 to confirm that PPR10 can block exonucleolytic RNA decay from both the 5' and 3' directions, as predicted by prior in vivo data. I also present evidence that PPR10 promotes translation by restructuring its RNA ligand to allow access to the ribosome. These findings illustrate how the unusually long RNA interaction surface predicted for PPR proteins can have diverse effects on RNA metabolism.
This dissertation includes both previously published and unpublished co-authored material.<br>Committee in charge: Eric Selker, Chairperson, Biology;
Alice Barkan, Advisor, Biology;
Victoria Herman, Member, Biology;
Karen Guillemin, Member, Biology;
J. Andrew Berglund, Outside Member, Chemistry
8
Oliver, Antony William. "The interaction of bacteriophage fd Gene 5 protein with specific nucleic acid sequences." Thesis, University of Portsmouth, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363110.
Full text
9
Nadassy, Katalin. "Molecular recognition by proteins : structural features of zinc and protein-nucleic acid binding sites." Thesis, University of Stirling, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341227.
Full text
10
Mussabekova, Assel. "Evaluating antiviral activity of nucleic acid binding proteins across species." Thesis, Strasbourg, 2019. http://www.theses.fr/2019STRAJ006.
Full textAbstract:
Le projet a permis d’identifier des répertoires de protéines interagissant avec différentes espèces d’acides nucléiques caractéristiques des virus chez cinq espèces animales (Homme, souris, poulet, drosophile, nématode). Ces protéines représentent des candidats pour remplir des fonctions de récepteurs de l’immunité innée ou de molécules antivirales. Certaines d’entre elles ont été conservées au cours de l’évolution, ce qui m’a permis de tester leur fonction dans la drosophile. J’ai réalisé un crible impliquant des infections avec cinq virus différents sur 100 protéines conservées. Ce crible m’a permis d’identifier huit protéines dont l’inhibition impacte la réplication virale. Deux d’entres elles, CG5641 et Zn72D, sont nécessaires pour la réplication des virus de type picornavirus (CrPV). Le candidat le plus intéressant identifié est cependant la protéine Tao, dont l’inhibition entraîne une augmentation de la réplication de virus appartenant à plusieurs familles, chez la drosophile et dans les cellules de mammifères<br>Antiviral response largely relies on the recognition of viral nucleic acids. The aim of the project was to characterize the range of nucleic acid binding proteins in the context of viral infection in flies. We identified a wide repertoire of proteins, which recognize viral nucleic acids in five species (human, mouse, chicken, fruit fly and roundworm). Among these proteins, there are ones, which are conserved in insects and humans, and therefore their function can be easily studied in the fruit fly model. Afterwards, we have performed a large screen in flies to study more precisely the function of 100 proteins in infection with 5 different viruses. We have found eight promising candidates as a result of this screen. We identified two Drosophila proteins CG5641 and Zn72D, which are also present in humans, as proviral factors. We also identified a protein Tao, which is conserved in humans, and is antiviral against several types of viruses
11
Almlöf, Martin. "Computational Methods for Calculation of Ligand-Receptor Binding Affinities Involving Protein and Nucleic Acid Complexes." Doctoral thesis, Uppsala University, Department of Cell and Molecular Biology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7421.
Full textAbstract:
<p>The ability to accurately predict binding free energies from computer simulations is an invaluable resource in understanding biochemical processes and drug action. Several methods based on microscopic molecular dynamics simulations exist, and in this thesis the validation, application, and development of the linear interaction energy (LIE) method is presented.</p><p>For a test case of several hydrophobic ligands binding to P450cam it is found that the LIE parameters do not change when simulations are performed with three different force fields. The nonpolar contribution to binding of these ligands is best reproduced with a constant offset and a previously determined scaling of the van der Waals interactions.</p><p>A new methodology for prediction of binding free energies of protein-protein complexes is investigated and found to give excellent agreement with experimental results. In order to reproduce the nonpolar contribution to binding, a different scaling of the van der Waals interactions is neccesary (compared to small ligand binding) and found to be, in part, due to an electrostatic preorganization effect not present when binding small ligands.</p><p>A new treatment of the electrostatic contribution to binding is also proposed. In this new scheme, the chemical makeup of the ligand determines the scaling of the electrostatic ligand interaction energies. These scaling factors are calibrated using the electrostatic contribution to hydration free energies and proposed to be applicable to ligand binding.</p><p>The issue of codon-anticodon recognition on the ribosome is adressed using LIE. The calculated binding free energies are in excellent agreement with experimental results, and further predict that the Leu2 anticodon stem loop is about 10 times more stable than the Ser stem loop in complex with a ribosome loaded with the Phe UUU codon. The simulations also support the previously suggested roles of A1492, A1493, and G530 in the codon-anticodon recognition process.</p>
12
Almlöf, Martin. "Computational methods for calculation of Ligand-Receptor binding affinities involving protein and nucleic acid complexes /." Uppsala : Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7421.
Full text
13
Bonthala, Venkata Suresh. "Translating nucleic acid binding protein function from model species to minor crops using transfer learning." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/52289/.
Full textAbstract:
Genomic elements such as proteins or genes are the basic unit of the genome and involved in the functioning of every biological process. Predicting, therefore, the function of these genomic elements is the first step in the understanding of functioning of plants under various stress conditions. To date, various types of computational methods have been developed to predict the function of a given protein sequence. The recent increase in the development of a number of methods has created its own set of problems leading to difficulty in applying on newly sequenced genomes especially non-model crops. Due to these reasons, the immediate requirement for development of sophisticated computational methods to predict the function of a given protein sequence is raised. This thesis presents three novel computational tools developed based on transfer learning algorithms to predict the function of a given protein sequence and these tools are: 1) TL-RBPPred, for prediction of RNA-binding proteins, outperformed SPOT-Seq, RNApred, RBPPred and BLASTp on HumanSet (AUC of 0.977), YeastSet (AUC of 0.971), ArabidopsisSet (AUC of 0.972) and GlymaxSet (AUC of 0.97); 2) TL-DBPPred, for prediction of DNA-binding proteins, outperformed DNABP, enDNA-Prot, iDNA-Prot, nDNAProt, iDNA-Prot|Dis, DNAbinder and BLASTp on an testing dataset (AUC of 0.988); and 3) TL-TFPred, for prediction of transcription factors, outperformed PlantTFcat, iTAK and BLASTp on testing dataset (AUC of 0.999) in terms of prediction accuracy. Further, both TL-RBPPred and TL-DBPPred were tested on the transcriptome of the non-model crop, Bambara groundnut (Vigna subterranea (L.) Verdc.), to identify RNA-binding and DNA-binding proteins, respectively. The results obtained from these tests indicated that these two methods outperformed in terms of prediction accuracy (AUC) as compared to existing current state-of-the art tools such as SPOT-Seq, RBPPred, iDNA-Prot and iDNA-Prot|Dis. Based on the performance, the developed methods will be useful in predicting the function of given protein sequences (DNA, RNA-binding and transcription factor) of model species as well as non-model crops.
14
Kokorelis, Steve H. "Biochemical Analysis of Putative Single-Stranded Nucleic Acid Binding Proteins in Porphyromonas gingivalis." VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/4833.
Full textAbstract:
Proteins that bind to both DNA and RNA embody the ability to perform multiple functions by a single gene product. These nucleic acid binding proteins in prokaryotes can play a vital role in many cellular processes, including replication, transcription, gene expression, recombination, and repair, to name a few. Nucleic acid binding proteins have unique functional characteristics that stem from their structural attributes that have evolved in a widely-conserved manner. In Escherichia coli (E. coli), the highly-conserved histone-like protein, HU, which predominates as a heterodimer of HUα and HUβ, has been found to bind to both dsDNA and ssDNA. Likewise, RNA-binding proteins contain various structural motifs, many of which are also conserved amongst many bacterial species like the RNA recognition motif. However, in Porphyromonas gingivalis, a periodontal pathogen, the histone-like, HU proteins and the RNA-binding protein (RBP) are not well characterized compared to their respective structures in E. coli. In our study, we sought to characterize and compare the HU proteins and RBP in order to gain a better understanding of their structure and function in the cell. Our data showed the HU proteins predominate as homo-tetramers and RBP as a monomer. We demonstrated single-stranded DNA binding with all three proteins. We found both P. gingivalis HU subunits bind non-specifically to ssDNA but show preferential binding to poly(dG) content, while binding to poly(dA) the weakest. These results show that HUα, HUβ and RBP are novel ssDNA binding proteins in P. gingivalis, indicating an expanded role and function within the cell.
15
Fai, Leonard Yenwong. "Subcellular Localization of Tobacco Salicylic Acid Binding Protein 2 in Plants." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/1274.
Full textAbstract:
Salicylic Acid Binding Protein 2 (SABP2) is a 29kDa protein present in extremely low amounts in tobacco leaves. SABP2 processes the mobile defense signal, methyl salicylic acid generated in plants resisting microbial infection. The precise localization of SABP2 in plants is not known. SABP2 has not been shown to have any targeting signal peptides. This study was designed to determine localization of SABP2 in tobacco plants. Biochemical and immunological studies using antibodies against SABP2 suggest that it is localized to the chloroplast, associating with chloroplast envelope membranes. Chloroplast import assays confirm that SABP2 is associated with the chloroplast envelope membrane. Solubilization and analysis of chloroplast membrane proteins show that imported SABP2 associates with the chloroplast envelope membrane by weak hydrophobic and/or ionic interactions. Cellular localization and understanding mechanisms of SABP2 import to the chloroplast will be important from a metabolic engineering standpoint to enhance plant natural defense against microbial pathogens.
16
Robertson, Timothy Allen. "Development and validation of statistical potential functions for the prediction of protein/nucleic-acid interactions from structure /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/9268.
Full text
17
Weber, Janine [Verfasser], та Klaus [Akademischer Betreuer] Förstemann. "Molecular characterization of the neuronal nucleic acid-binding protein Pur-α / Janine Weber. Betreuer: Klaus Förstemann". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://d-nb.info/1074358805/34.
Full text
18
Yuh, Joannes Petrus. "Effect of Pesticides on Salicylic Acid Binding Protein 2 (SABP2) and Plant Defense." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/2259.
Full textAbstract:
Tobacco SABP2 has been shown to display high affinity for salicylic acid (SA) and methylsalicylate (MeSA) and plays an important role in SAR signal development. Using biochemical approach, SABP2 has been shown to demonstrate strong esterase activity in converting MeSA to SA. Recent study shows that tetra fluoroacetophenone, a synthetic analog of SA, competitively inhibits SABP2 esterase activity as well as suppresses SAR signal development in tobacco mosaic virus (TMV)-infected tobacco plants. Not much has been studied on the effect of pesticides on plant defenses. Because both AChE and SABP2 are esterase-like proteins belonging to α/β hydroxylase superfamily, we hypothesize that pesticides may inhibit the MeSA esterase activity of SABP2 and block SAR development. Biochemical and molecular biology techniques were used to test this hypothesis. SAR in tobacco-TMV plant-pathogen system is measured by significant decrease in TMV-induced lesion sizes in secondarily inoculated distal leaves.
19
Papp, Laura V., and n/a. "Multiple Levels of Regulation of Human SECIS Binding Protein 2, SBP2." Griffith University. School of Biomolecular and Biomedical Science, 2006. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20070208.145623.
Full textAbstract:
Selenium is an essential trace mineral of fundamental importance to human health. Its beneficial functions are largely attributed to its presence within a group of proteins named selenoproteins in the form of the amino acid selenocysteine (Sec). Recently, it was revealed that the human selenoproteome consists of 25 selenoproteins, and for many of them their function remains unknown. The most prominent known roles of selenoproteins are to maintain the intracellular redox homeostasis, redox regulation of intracellular signalling and thyroid hormone metabolism. Sec incorporation into selenoproteins employs a unique mechanism that involves decoding of the UGA stop codon. The process requires interplay between distinct, intrinsic features such as the Sec Insertion Sequence (SECIS) element, the tRNASec and multiple protein factors. The work presented in this thesis has focused on characterising the regulation of human SECIS binding protein 2, SBP2, a factor central to this process. Experimental approaches combined with bioinformatics analysis revealed that SBP2 is subjected to alternative splicing. A total of nine alternatively spliced transcripts appear to be expressed in cells, potentially encoding five different protein isoforms. The alternative splicing events are restricted to the 5?-region, which is proposed to be dispensable for Sec incorporation. One of the variants identified, contains a mitochondrial targeting sequence that was capable of targetting SBP2 into the mitochondrial compartment. This isoform also appears to be expressed endogenously within the mitochondria in cells. Previous reports have depicted SBP2 as a ribosomal protein, despite the presence of a putative Nuclear Localisation Signal (NLS). In this study it was found that SBP2 subcellular localisation is not restricted to ribosomes. Intrinsic functional NLS and Nuclear Export Signals (NESs), enable SBP2 to shuttle between the nucleus and the cytoplasm via the CRM1 pathway. In addition, the subcellular localisation of SBP2 appears to play an important role in regulating Sec incorporation into selenoproteins. The subcellular localisation of SBP2 is altered by conditions imposing oxidative stress. Several oxidising agents induce the nuclear accumulation of SBP2, which occurs via oxidation of cysteine residues within a novel redox-sensitive cysteine rich domain (CRD). Cysteine residues were to form disulfide bonds and glutathione-mixed disulfides during oxidising conditions, which are efficiently reversed in vitro by the thioredoxin and glutaredoxin systems, respectively. These modifications negatively regulate selenoprotein synthesis. Cells depleted of SBP2 are more sensitive to oxidative stress than control cells, which correlated with a substantial decrease in selenoprotein synthesis after treatment with oxidising agents. These results provide direct evidence that SBP2 is required for Sec incorporation in vivo and suggest that nuclear sequestration of SBP2 under such conditions may represent a mechanism to regulate the expression of selenoproteins. Collectively, these results suggest that SBP2 is regulated at multiple levels: by alternative splicing, changes in subcellar localisation and redox control.
20
Vreeland, Amanda C. "Cellular Retinoic Acid-Binding Protein 2 Cooperates with HuR to Stabilize RNA and Inhibit Tumor Growth." Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1409933949.
Full text
21
Okeke, Joy C. "The Effects of Ellagic Acid on Insulin-Like Growth Factor Binding Protein-2 in Human Prostate Cancer Cells." Bowling Green State University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1162343994.
Full text
22
Chapagai, Danda P. "Biochemical Characterization of SBIP-470 and its role in SA-mediated Signaling in Plants." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etd/2428.
Full textAbstract:
Salicylic acid binding protein 2 (SABP2) is known to play a key role in Salicylic acid mediated defense pathway. SBIP-470 is SABP2 interacting protein that might be putatively involved in transfer of lipids. SBIP-470 was cloned without the signal peptide and expressed in E. coli. In vitro lipid binding assay using recombinant SBIP-470 failed to detect lipid binding. In vitro lipid transfer assay showed recombinant SBIP-470 does not transfer phospholipid. Study has shown that SBIP-470 is highly inducible upon infection with viral as well as bacterial pathogens. Induction of SBIP-470 expression upon the TMV infection most likely depends upon the SABP2 while its expression upon non-host bacterial pathogens is most probably inhibited by the SABP2. A study of Arabidopsis knockout mutants (ltp12 mutant and ltp2 mutant) lacking the SBIP-470 homolog genes showed defects in growth phenotype, and they were found susceptible to bacterial pathogens.
23
Amjad, Arshi. "Analysis of cellular retinoic acid binding protein 2 expression in dermal fibroblasts; role in non-healing of chronic wounds." Thesis, Örebro universitet, Institutionen för hälsovetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-59103.
Full textAbstract:
Abstract Chronic, non-healing wounds constitute a massive financial burden on health care system. The healing processes of these wounds and their underlying pathology are only partly understood. In this study, important biological functions performed by Retinoic acid with its regulatory protein cellular retinoic acid binding protein 2 (CRABP2) were discussed. Possibly, these biological func-tions might be linked with chronic wound therapeutic by inducing antiproliferative activity of cells which leads to reduction in migration and growth rate of fibroblast during skin regeneration pro-cess in chronic wound healing. The aim of this study was to comparatively analyze the expression pattern of CRABP2 and P16 cyclic dependent kinase inhibitor in dermal fibroblasts at mRNA levels along with their morphological pattern, migration and growth rate. Fibroblasts were cultured and their morphology were observed by phase-contrast imaging. Difference in viability, migratory capacity was examined by Cell titer blue and scratch assay respectively and expression were meas-ured by polymerase chain reaction. Interestingly, the date revealed that morphology was altered and growth rate and migration velocity was significantly lower in chronic wound fibroblasts and senescent fibroblasts when compared with their control. Expression pattern revealed that CRABP2 was highly up-regulated only by senescent cells but not in chronic wound fibroblasts which point novel function for this protein in term of replicative senescence. However, P16 was not signifi-cantly altered among all fibroblasts which demands supplementary studies to conform the role of CRABP2 in fibroblast dysfunction and cellular senescence in chronic wounds.
24
Cramer, Jason. "EVOLUTION AND DIVERGENCE OF THE STRUCTURAL AND PHYSICAL PROPERTIES OF DNA BINDING BY METHYL-CYTOSINE BINDING DOMAIN FAMILY MEMBERS 2 AND 3." VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3517.
Full textAbstract:
The studies presented in this dissertation, Evolution And Divergence Of The Structural And Physical Properties Of DNA Binding By Methyl-Cytosine Binding Domain Family Members 2 And 3, pertain primarily to two key epigenetic regulators involved with the biological interpretation of methylated DNA marks. We provide insights into the emergence and evolution of the MBD2 and MBD3 and how those molecular entities influence heritable changes in gene activity. We further provide details regarding the mystery surrounding MBD3 function and the MBD2-mediated capacity of primitive animals to carry out methylation-specific epigenetic mechanisms. In chapter two, we describe the DNA binding properties of MBD2 and MBD3. This study provides information regarding previously unidentified MBD3 binding properties and potential biological function. In chapter three, we show that sponges demonstrate a MBD2-mediated capacity for binding methylated DNA sites, recruit NuRD components in vitro, and knockdown of MBD2 in the freshwater desmosponge, Ephydatia muelleri, promotes an abnormal growth phenotype.
25
Cherry, Melissa A. "Sequence dependence of the activity of amphipathic peptides." View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-2/rp/cherrym/melissacherry.pdf.
Full text
26
Almqvist, Jenny. "Epstein-Barr virus nuclear antigen 1, Oct & Groucho/TLE in control of promoter regulation /." Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-523-2/.
Full text
27
Kilcullen, Niamh. "Heart-type fatty acid-binding protein (H-FABP) and matrix metalloproteinase-2 (MMP-2) in diagnosis and risk stratification in patients with acute coronary syndromes." Thesis, University of Leeds, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434465.
Full text
28
Filiano, Anthony J. "The protective role of transglutaminase 2 in ischemic stroke." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2009. https://www.mhsl.uab.edu/dt/2009p/filiano.pdf.
Full text
29
Dean, S. J. "An investigation in to the role of fatty acid binding protein-7, insulin like growth factor binding protein-2 and phosphatase and tensin homolog in triple negative breast cancer, in vitro and in vivo." Thesis, University of the West of England, Bristol, 2014. http://eprints.uwe.ac.uk/23010/.
Full textAbstract:
Introduction Triple negative breast cancers are defined by their lack of expression of HER, oestrogen receptors and progesterone receptors. They account for around 10-24% of cases. To define a cancer by the biomarkers it does not express is unsatisfactory. Triple negative breast cancer has been linked to aspects of metabolism and metabolic disorders such as diabetes. There are several biomarkers that are of interest and overlap in both their roles in breast cancer and in aspects of metabolism. Fatty acid binding protein 7 (FABP7) is one of 9 FABPs that is involved in the transport, solubilisation and regulation of metabolism of various fatty acids. Expression profiling and immunohistochemistry (IHC) studies have identified FABP7 to be over-expressed in a subtype of breast cancer that can be considered almost synonymous with triple negative breast cancer; basal-like breast cancer, so called because it expresses cytokeratins that are characteristic of basal epithelial cells. The role of FABP7 in breast cancer is not fully understood and studies have given conflicting results in regards to the relation to prognosis. Evidence suggests that FABP7 can be regulated by methylation acetylation and exposure to fatty acids. Insulin like growth factor binding protein-2 (IGFBP-2) is a member of the IGF-axis that is responsible for altering cell growth and metabolism. IGFBP-2 has been found to be over-expressed in many cancers including those of the prostate and breast. Phosphotensin homolog (PTEN) is a tumour suppressor gene that is responsible for dephosphorylating PIP3 to inhibit the Akt pathway and thus inhibit cell growth and promote apoptosis. IGFBP-2 has IGF independent actions; it can down-regulate PTEN through binding of an integrin receptor and therefore have mitogenic and anti-apoptotic effects. Aims To study the expression of the metabolic biomarkers FABP7, IGFBP-2 and PTEN in clinical cases of Malaysian TN breast cancer. To use appropriate cell lines in order to more fully understand whether epigenetic mechanisms and FAs regulate FABP7 expression. To over-express FABP7 in a breast cancer cell lines and to further understand the role of FABP7 in breast cancer. Methods IHC was used to assess FABP7, PTEN and IGFBP-2 expression in a cohort of triple negative breast cancer cases. FAs, a demethylation agent-AZA and a histone deacetylase inhibitor-TSA were used to investigate what regulated FABP7 in cell lines. Over-expression experiments were used to understand the effect of FABP7 in breast cancer cell lines. Results FABP7 expression in patient samples was associated with lower grade, basal-like phenotype, FAS expression and although not significant, improved patient survival. Treatment of BT-20 and MDA-MB-231 cell lines with AZA and TSA resulted in increases in FABP7 mRNA expression. Fatty acid treatment led to changes in FABP7 mRNA expression. Combinations of AZA and fatty acids gave large increases in FABP7 mRNA expression. Over-expression of FABP7 in BT-20 cells resulted in increased cell viability and although not significant changes in expression of survivin, caspase 9 and their splice variants. IGFBP-2 expression was associated with poor patient survival though this was not significant. PTEN loss was a frequent event in the cohort of triple negative breast cancer cases; 48.3% of cases had PTEN loss. PTEN loss was associated with poor patient survival though this was not significant. PTEN loss was associated with expression of IGFBP-2. Discussion & Conclusions FABP7 is likely to play a role in patient survival as demonstrated in the patient samples. FABP7 over-expressing BT-20 cells tended to have increased survivin FL and ΔEX3 expression. Both increased mitochondrial activity and survivin expression have been found to be associated with improved prognosis in breast cancer and this may explain some mechanisms by which FABP7 results in better prognosis in the TN breast cancer cases in this study. Since FABP7 mRNA expression was not increased to fold changes comparable to oestrogen receptor re-expression after AZA and TSA treatment, it is unlikely that the FABP7 gene is methylated or regulated by acetylation. It is possible that there are genes upstream of FABP7 such as transcription factors that are regulated my methylation and acetylation and therefore impact on FABP7 expression after treatment with AZA and TSA. This is the first study that demonstrates the significant relationship between IGFBP-2 expression and PTEN loss in patient samples. PTEN loss is a frequent event in TN breast cancer. IGFBP-2 and PTEN loss may be useful markers of prognosis in TN breast cancer.
30
Griffiths, Genevieve S. "Investigating the impact and mechanism of vesicular and non-vesicular mediated GPI-linked protein transfer from reproductive luminal fluids to sperm, using SPAM1 as a model." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 119 p, 2007. http://proquest.umi.com/pqdweb?did=1397900391&sid=22&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Full text
31
Ozkurt, Ibrahim Cem. "Adenovirus E4 promoter binding protein/nuclear factor regulated by IL-3 (E4BP4) expression and function in osteoblasts." Diss., Restricted to subscribing institutions, 2004. http://proquest.umi.com/pqdweb?did=828432751&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
Full text
32
Gimenez, Rodrigo Pinto 1966. "Expressão proteica da adiponectina, receptores de adiponectina tipos 1 e 2 e da adipocyte fatty acid binding protein no carcinoma invasor, nas suas lesões precursoras e nas lesões benignas da mama = Protein expression of adiponectin, adiponectin receptors types 1 and 2 and adipocyte fatty acid binding protein in breast cancer, its precursor lesions and benign breast lesions." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/311116.
Full textAbstract:
Orientadores: Maria Salete Costa Gurgel, Sílvia de Barros-Mazon<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas<br>Made available in DSpace on 2018-08-22T03:12:53Z (GMT). No. of bitstreams: 1
Gimenez_RodrigoPinto_D.pdf: 2727620 bytes, checksum: 505f7780aca2f535e4882eb250f83b9d (MD5)
Previous issue date: 2013<br>Resumo: Introdução: A obesidade tem se mostrado responsável pelo aumento de 30% a 50% dos casos novos de câncer de mama, em particular na pós-menopausa. A mais recente hipótese para explicar tal fato situa os adipócitos e suas funções autócrina, parácrina e endócrina no centro do cenário, através da relação das adipocinas, por ele secretadas, com a obesidade e o câncer de mama. Objetivo: Artigo 1- Comparar o padrão de expressão imunoistoquímica da adiponectina (APN) e dos seus receptores tipos 1 e 2 (adipoR1/R2) no carcinoma invasor (CDI), carcinoma ductal in situ (CDIS) e lesões benignas da mama (BE) e correlacioná-los com parâmetros clínicos e histológicos. Artigo 2- Avaliar a expressão protéica da FABP4 nos tecidos epiteliais e adiposos mamário de portadoras de CDI, CDIS e lesões benignas da mama. Material e Métodos: Foram incluídos os blocos de parafina de 223 mulheres sendo 69 com CDI, 73 com CDIS e 81 com biópsias negativas para câncer de mama, tratadas no CAISM/UNICAMP de janeiro de 2008 a dezembro de 2011, e preparadas lâminas de Tissue Microarray (TMA). A expressão de APN e Adipo R1/R2 foi avaliada no tecido tumoral nos casos CDI e CDIS e no tecido epitelial e nos casos benignos. A expressão de FABP4 foi avaliada no tecido tumoral, na gordura peritumoral (GP) e na gordura mamária distante (GD) nos casos de CDI e CDIS, e no tecido epitelial e gorduras mamários nos casos benignos. Para avaliar uma possível relação entre a expressão dos marcadores entre si e com parâmetros antropométricos, clínicos e histopatológicos, foram utilizados os testes qui-quadrado ou exato de Fisher, Mann-Whitney, Kruskal-Wallis e correlação de Spearman. As determinações foram calculadas considerando o valor de ?=0,05 (p<0,05). Resultados: Artigo 1 - A APN mostrou-se expressa em 65% dos CDI, 48% dos CDIS e 12% das BE e AdipoR1 em 98%, 94% e 71%, respectivamente. Todos os casos de CDI e CDIS expressaram AdipoR2 contra 81% de BE. Nos CDI e CDIS observou-se associação entre maior expressão de APN e tumores RE negativo. No CDIS esta associação foi também observada com RP negativo. Artigo 2 - Observou-se expressão protéica da FABP4 no tecido epitelial em 90% dos CDI, 40% dos CDIS e 28% em BE. Considerando-se a GP e GD esta expressão foi maior nas BE que nos CDI, diferenças consideradas significativas. Nas pacientes com CDI a expressão da FABP4 foi maior quando o diagnóstico ocorreu até 50 anos de idade. A totalidade dos casos expressou moderada a intensamente este marcador no tecido gorduroso periepitelial e distante. Conclusões: As diferenças de expressões protéicas da adiponectina e dos seus receptores AdipoR1/R2 observadas em diferentes diagnósticos mamários sugerem sua participação no complexo mecanismo etiológico destas diferentes condições. Os resultados deste estudo indicam, ainda, que existe uma correlação direta entre expressão protéica da FABP4, câncer de mama e obesidade<br>Abstract: Introduction: Obesity has been shown to be responsible for a 30 to 50% increase in new breast cancer cases, in particular in the postmenopausal period. The most recent hypothesis that explains this fact places adipocytes and its autocrine, paracrine and endocrine functions at center stage, linking adipokines secreted by adipocytes to obesity and breast cancer. Objective: Article 1- to compare immunohistochemistry expression pattern of adiponectin (APN) and its receptors types 1 and 2 (adipoR1/R2) in invasive carcinoma (IDC), ductal carcinoma in situ (CDIS) and benign breast lesions (BE), correlated with clinical and histological parameters. Article 2- To assess FABP4 protein expression in epithelial and adipose breast tissue in women diagnosed with IDC, DCIS and benign breast lesions. Material and Methods: Paraffin-embedded blocks from 223 women were included. Of the total number of women, 69 had IDC CDI, 73 had CDIS and 81 had biopsies negative for breast cancer. The patients have been treated at CAISM/Unicamp from January 2008 to December 2011 and Tissue Microarray (TMA) slides were constructed. Expression of APN and Adipo R1/R2 was assessed in tumor tissue in cases of IDC and DCIS and in epithelial tissue in benign cases. FABP4 expression was evaluated in tumor tissue, peritumoral fat tissue (PF) and distant fat breast tissue (DF) in cases of IDC and DCIS and in the epithelial tissue and breast fat tissue in benign cases. To assess a possible relationship between marker expression and anthropometric, clinical and histopathological parameters, the chi-square test or Fisher's exact test, Mann-Whitney test, Kruskal-Wallis test and Spearman's correlation were used. Determinations were calculated, considering a value ?=0.05 (p<0.05) as significant. Results: Article 1 - APN was shown to be expressed in 65% of IDC, 48% of DCIS and 12% of BE and AdipoR1 in 98%, 94% and 71%, respectively. All IDC and DCIS cases expressed AdipoR2 versus 81% of BE. In IDC and DCIS, an association between a higher level of APN expression and ER-negative tumors was observed. In DCIS, this association was also observed with PR-negative tumors. Article 2 - FABP4 protein expression was observed in epithelial tissue in 90% of CDI, 40% of DCIS and 28% of BE. Considering PF and DF, FABP4 expression had a higher level in BE than in IDC, a difference that was considered significant. In patients with IDC, FABP4 expression was higher when diagnosis was made in patients aged up to 50 years. In all cases, this marker was moderately to intensely expressed in the peri-epithelial and distant fat tissue. Conclusions: Discrepancies in protein expression of adiponectin and its receptors AdipoR1/R2 observed in different breast diagnoses suggest its participation in the complex etiologic mechanism of these different conditions. Our results indicate that there is a direct correlation between FABP4 protein expression, breast cancer and obesity<br>Doutorado<br>Oncologia Ginecológica e Mamária<br>Doutor em Ciências da Saúde
33
Kops, Natália Luiza. "Consumo alimentar e perfil lipídico de pacientes candidatos à cirurgia bariátrica, portadores ou não do alelo Thr54 do gene Fatty Acid Binding Protein-2." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/143626.
Full text
34
Humphrey, Peter Saah. "Signal transduction mechanisms for stem cell differentation into cardiomyocytes." Thesis, University of Hertfordshire, 2009. http://hdl.handle.net/2299/3760.
Full textAbstract:
Cardiovascular diseases are among the leading causes of death worldwide and particularly in the developed World. The search for new therapeutic approaches for improving the functions of the damaged heart is therefore a critical endeavour. Myocardial infarction, which can lead to heart failure, is associated with irreversible loss of functional cardiomyocytes. The loss of cardiomyocytes poses a major difficulty for treating the damaged heart since terminally differentiated cardiomyocytes have very limited regeneration potential. Currently, the only effective treatment for severe heart failure is heart transplantation but this option is limited by the acute shortage of donor hearts. The high incidence of heart diseases and the scarcity donor hearts underline the urgent need to find alternative therapeutic approaches for treating cardiovascular diseases. Pluripotent embryonic stem (ES) cells can differentiate into functional cardiomyocytes. Therefore the engraftment of ES cell-derived functional cardiomyocytes or cardiac progenitor cells into the damaged heart to regenerate healthy myocardial tissues may be used to treat damaged hearts. Stem cell-based therapy therefore holds a great potential as a very attractive alternative to heart transplant for treating heart failure and other cardiovascular diseases. A major obstacle to the realisation of stem cell-based therapy is the lack of donor cells and this in turn is due to the fact that, currently, the molecular mechanisms or the regulatory signal transduction mechanisms that are responsible for mediating ES cell differentiation into cardiomyocytes are not well understood. Overcoming this huge scientific challenge is absolutely necessary before the use of stem cell-derived cardiomyocytes to treat the damaged heart can become a reality. Therefore the aim of this thesis was to investigate the signal transduction pathways that are involved in the differentiation of stem cells into cardiomyocytes. The first objective was the establishment and use of cardiomyocyte differentiation models using H9c2 cells and P19 stem cells to accomplish the specific objectives of the thesis. The specific objectives of the thesis were, the investigation of the roles of (i) nitric oxide (ii) protein kinase C (PKC), (iii) p38 mitogen-activated protein kinase (p38 MAPK) (vi) phosphoinositide 3-kinase (PI3K) and (vi) nuclear factor-kappa B (NF-kB) signalling pathways in the differentiation of stem cells to cardiomyocytes and, more importantly, to identify where possible any points of convergence and potential cross-talk between pathways that may be critical for differentiation to occur. P19 cells were routinely cultured in alpha minimal essential medium (α-MEM) supplemented with 100 units/ml penicillin /100 μg/ml streptomycin and 10% foetal bovine serum (FBS). P19 cell differentiation was initiated by culturing the cells in microbiological plates in medium containing 0.8 % DMSO to form embryoid bodies (EB). This was followed by transfer of EBs to cell culture grade dishes after four days. H9c2 cells were cultured in Dulbecco’s Modified Eagle’s medium (DMEM) supplemented with 10% FBS. Differentiation was initiated by incubating the cells in medium containing 1% FBS. In both models, when drugs were employed, they were added to cells for one hour prior to initiating differentiation. Cell monolayers were monitored daily over a period of 12 or 14 days. H9c2 cells were monitored for morphological changes and P19 cells were monitored for beating cardiomyocytes. Lysates were generated in parallel for western blot analysis of changes in cardiac myosin heavy chain (MHC), ventricular myosin chain light chain 1(MLC-1v) or troponin I (cTnI) using specific monoclonal antibodies. H9c2 cells cultured in 1% serum underwent differentiation as shown by the timedependent formation of myotubes, accompanied by a parallel increase in expression of both MHC and MLC-1v. These changes were however not apparent until 4 to 6 days after growth arrest and increased with time, reaching a peak at day 12 to 14. P19 stem cells cultured in DMSO containing medium differentiated as shown by the timedependent appearance of beating cardiomyocytes and this was accompanied by the expression of cTnI. The differentiation of both P19 stem cells and H9c2 into cardiomyocytes was blocked by the PI3K inhibitor LY294002, PKC inhibitor BIM-I and the p38 MAPK inhibitor SB2035800. However when LY294002, BIM-I or SB2035800 were added after the initiation of DMSO-induced P19 stem cell differentiation, each inhibitor failed to block the cell differentiation into beating cardiomyocytes. The NF-kB activation inhibitor, CAPE, blocked H9c2 cell differentiation into cardiomyocytes. Fast nitric oxide releasing donors (SIN-1 and NOC-5) markedly delayed the onset of differentiation of H9c2 cells into cardiomyocytes while slow nitric oxide releasing donors (SNAP and NOC-18) were less effective in delaying the onset of differentiation or long term differentiation of H9c2 cells into cardiomyocytes. Akt (protein kinase B) is the key downstream target of PI3K. Our cross-talk data also showed that PKC inhibition and p38 MAPK inhibition respectively enhanced and reduced the activation of Akt, as determined by the phosphorylation of Akt at serine residue 473. In conclusion, PKC, PI3K, p38 MAPK and NF-kB are relevant for the differentiation of stem cells into cardiomyocytes. Our data also show that the PKC, PI3K and p38 MAPK signalling pathways are activated as very early events during the differentiation of stem cells into cardiomyocytes. Our data also suggest that PKC may negatively regulate Akt activation while p38 MAPK inhibition inhibits Akt activation. Our fast NO releasing donor data suggest that nitric oxide may negatively regulate H9c2 cell differentiation.
35
Xiao, Xiaodong. "NIT-2, the major positive regulatory protein of the Neurospora crassa nitrogen control circuit : DNA binding, nuclear localization, and interaction with NMR /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487861396025639.
Full text
36
Laggai, Stephan [Verfasser], and Alexandra K. [Akademischer Betreuer] Kiemer. "Hepatic steatosis and cancer development : role of insulin-like growth factor 2 mRNA binding protein p62, IGF2BP2, IMP2-2 and fatty acid elongase ELOVL6 / Stephan Laggai. Betreuer: Alexandra K. Kiemer." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2014. http://d-nb.info/1059390469/34.
Full text
37
Tranchant, Thierry. "Caracterisation et etude fonctionnelle de la fabp (fatty acid binding protein) membranaire des cellules caco-2 en culture. Effets des acides gras polyinsatures a longue chaine." Tours, 1997. http://www.theses.fr/1997TOUR3302.
Full text
38
Jüngling, Niklas Frank [Verfasser]. "Untersuchung von Expression und prognostischer Relevanz von cellu-lar-retinoic-acid-binding protein 2 (CRABP2), retinoic-acid-receptor α (RARα), Östrogenrezeptor α ( ERα) und Progesteronrezeptor (PR) bei benignen und malignen Ovarialtumoren / Niklas Frank Jüngling". Kiel : Universitätsbibliothek Kiel, 2019. http://d-nb.info/1176518917/34.
Full text
39
Gupta, Sanjay Kumar [Verfasser], Stefan [Gutachter] Juranek, Utz [Gutachter] Fischer, and Markus [Gutachter] Landthaler. "The human CCHC-type Zinc Finger Nucleic Acid Binding Protein (CNBP) binds to the G-rich elements in target mRNA coding sequences and promotes translation / Sanjay Kumar Gupta ; Gutachter: Stefan Juranek, Utz Fischer, Markus Landthaler." Würzburg : Universität Würzburg, 2017. http://d-nb.info/1142789705/34.
Full text
40
Madera, Dmitri. "Cooperating Events in Core Binding Factor Leukemia Development: A Dissertation." eScholarship@UMMS, 2011. https://escholarship.umassmed.edu/gsbs_diss/532.
Full textAbstract:
Leukemia is a hematopoietic cancer that is characterized by the abnormal differentiation and proliferation of hematopoietic cells. It is ranked 7th by death rate among cancer types in USA, even though it is not one of the top 10 cancers by incidence (USCS, 2010). This indicates an urgent need for more effective treatment strategies. In order to design the new ways of prevention and treatment of leukemia, it is important to understand the molecular mechanisms involved in development of the disease.
In this study, we investigated mechanisms involved in the development of acute myeloid leukemia (AML) that is associated with CBF fusion genes. The RUNX1 and CBFB genes that encode subunits of a transcriptional regulator complex CBF, are mutated in a subset (20 – 25%) of AML cases. As a result of these mutations, fusion genes called CBFB-MYH11 and RUNX1-ETO arise. The chimeric proteins encoded by the fusion genes provide block in proliferation for myeloid progenitors, but are not sufficient for AML development. Genetic studies have indicated that activation of cytokine receptor signaling is a major oncogenic pathway that cooperates in leukemia development. The main goal of my work was to determine a role of two factors that regulate cytokine signaling activity, the microRNA cluster miR-17-92 and the thrombopoietin receptor MPL, in their potential cooperation with the CBF fusions in AML development.
We determined that the miR-17-92 miRNA cluster cooperates with Cbfb-MYH11 in AML development in a mouse model of human CBFB-MYH11 AML. We found that the miR-17-92 cluster downregulates Pten and activates the PI3K/Akt pathway in the leukemic blasts. We also demonstrated that miR-17-92 provides an anti-apoptotic effect in the leukemic cells, but does not seem to affect proliferation. The anti-apoptotic effect was mainly due to activity of miR-17 and miR-20a, but not miR-19a and miR-19b.
Our second study demonstrated that wild type Mpl cooperated with RUNX1-ETO fusion in development of AML in mice. Mpl induced PI3K/Akt, Ras/Raf/Erk and Jak2/Stat5 signaling pathways in the AML cells. We showed that PIK3/Akt pathway plays a role in AML development both in vitro and in vivo by increasing survival of leukemic cells. The levels of MPL transcript in the AML samples correlated with their response to thrombopoietin (THPO). Moreover, we demonstrated that MPL provides pro-proliferative effect for the leukemic cells, and that the effect can be abrogated with inhibitors of PI3K/AKT and MEK/ERK pathways.
Taken together, these data confirm important roles for the PI3K/AKT and RAS/RAF/MEK pathways in the pathogenesis of AML, identifies two novel genes that can serve as secondary mutations in CBF fusions-associated AML, and in general expands our knowledge of mechanisms of leukemogenesis.
41
Hossain, Mir Ashad. "Does SABP2 Exist As a Dimer?" Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/2255.
Full textAbstract:
Salicylic acid binding protein 2 (SABP2) is one of the key enzymes in salicylic acid-dependent plant defense pathway. SABP2 is a 29 kDa protein present in extremely low abundance in plants and it catalyzes the conversion of signaling molecule methyl salicylate into salicylic acid. Although it has been shown that 6x His-tagged SABP2 over expressed in E. coli is a homodimer, its exact conformation in planta is still unknown. Therefore, we proposed to determine if SABP2 exist as a dimer and/or monomer under natural condition. To verify the exact conformation of native SABP2 protein in plant, SABP2 was purified from wild type tobacco using a 5-step purification protocol. Analysis of purified SABP2 in gel filtration and immunoblot assay suggested that SABP2 exists as a monomer in tobacco plant. Studies on SABP2 conformation will give us insight into the structure and functional relationship of this protein in salicylic acid-dependent disease resistance pathway.
42
Sharma, Rajhans. "Caractérisation et ciblage de la reconnaissance dynamique de Trp37-G lors de l’interaction de la protéine NCp7 de HIV-1 avec des acides nucléiques." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAJ014.
Full textAbstract:
La protéine de la nucléocapside (NC) possède un rôle important dans le cycle de viral du VIH-1 grâce à sa propriété chaperone des acides nucléiques (NA) qui implique la reconnaissance de son résidu Trp37 avec un résidu Guanine de l'acide nucléique cible. Nous avons caractérisé cette reconnaissance dynamique Trp37-G en utilisant des séquences impliquées dans la transcription inverse et l'assemblage de l'ARN génomique. En utilisant les analogues nucléosidiques fluorescents thienoguanosine (thG) et 2-thiényl-3-hydroxychromone (3HCnt), nous avons déterminé l'ensemble des constantes de vitesse cinétiques du mécanisme d’hybridation de la séquence (-)PBS avec (+)PBS en absence et en présence de NC. Nous avons également étudié le rôle du NA sucre dans les complexes NC-ARN et NC-ADN, puisque la protéine NC se lie avec la polarité opposée aux séquences d'ADN et d'ARN. Nous avons confirmé que l'interaction du résidu Trp37 avec les amino-acides de type guanines était critique lors de la formation des complexes avec les deux mutants d’ARN et d’ADN de PBS et de SL3. Enfin, nous avons réalisé un criblage de potentiels inhibiteurs de la protéine NC et examiné les touches identifiées à partir d’un test basé sur la fluorescence de la sonde thG<br>Nucleocapsid protein (NC) plays crucial roles in HIV-1 life cycle through its nucleic acid (NA) chaperoning property that involves recognition of it’s Trp37 residue with a Guanine residue of the target nucleic acid sequences. Herein, we characterized this dynamic Trp37-G recognition with sequences involved in reverse transcription and genomic RNA packaging. Using the fluorescent thienoguanosine (thG) and 2-thienyl-3-hydroxychromone (3HCnt) nucleoside analogues, we determined the whole set of kinetic rate constants for annealing of (-)PBS with (+)PBS in the absence and presence of NC. We also investigated the role of NA sugar in NC-RNA and NC-DNA complexes, as NC binds with opposite polarity to DNA and RNA sequences. We confirmed that the interaction of the Trp37 residue with guanines was critical for the formation of complexes with both RNA and DNA variants of PBS and SL3. Finally, we performed screening of NC inhibitors and tested the selected hits on a thG-based assay
43
Thakuri, Bal Krishna Chand. "SIP-428, a SIR2 Deacetylase Enzyme and Its Role in Biotic Stress Signaling Pathway." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etd/3505.
Full textAbstract:
SABP2 (Salicylic Acid Binding Protein 2) plays a vital role in the salicylic acid signaling pathway of plants both regarding basal resistance and systemic acquired resistance against pathogen infection. SIP-428 (SABP2 Interacting Protein-428) is a Silent information regulator 2 (SIR2) like deacetylase enzyme that physically interacts with SABP2 in a yeast two-hybrid interaction and confirmed independently by a GST pull-down assay. We demonstrated that SIP- 428 is an NAD+ dependent SIR2 deacetylase enzyme. Transgenic tobacco plants silenced in SIP- 428 expression via RNAi showed enhanced basal resistance to microbial pathogens. Moreover, these SIP-428-silenced lines also exhibited a robust induction of systemic acquired resistance. In contrast, the transgenic tobacco lines overexpressing SIP-428 showed compromised basal resistance and failed to induce systemic acquired resistance. These results indicate that SIP-428 is likely a negative regulator of SA-mediated plant immunity. Experiments using a SABP2 inhibitor showed that SIP-428 likely functions upstream of SABP2 in the salicylic acid signaling pathway. It also indicates that SABP2 is dependent on SIP-428 for its role in the SA signaling pathway. Subcellular localization studies using confocal microscopy and subcellular fractionation showed that SIP-428 localized in the mitochondria. These results clearly show a role for SIP-428 in plant immunity.
44
Nilsson, Maria. "Estrogen and liver X receptors in human disease /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-976-9/.
Full text
45
Marafona, Ana Marlene Neto. "The novel LAP1: TRF2 complex is associated to DNA damage." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/22000.
Full textAbstract:
Mestrado em Biomedicina Molecular<br>Lamin associated protein 1 (LAP1) is a type II integral membrane protein located at the inner nuclear membrane (INM). The role of LAP1 remains poorly understand, however, this protein has been associated with several cellular functions due to its interactions with lamins, phosphatase protein 1 (PP1), emerin and torsinA. Moreover, novel putative LAP1 interactors are emerging. A recent study from our group allowed the identification of several novel putative LAP1 interactors involved in telomere signaling and DNA damage responses, namely Ataxia-telangiectasia mutated (ATM), Telomeric repeat binding factor 2 (TRF2), Repressor Activator Protein 1 (RAP1), RAP1 interacting factor 1 homologue (RIF1), Mitotic arrest deficient-like1 (MAD2L1) and Mitotic arrest deficient-like1 binding protein (MAD2L1BP). Protein-protein interactions are crucial in the study of signaling pathways. In this study, TRF2 was identified as a novel LAP1 binding protein using both co-immunoprecipitations and mass spectrometry based methodologies. To determine the functional relevance of the novel complex LAP1:TRF2, HeLa cells were subjected to DNA damage using hydrogen peroxide (H2O2), namely double-stranded breaks (DSBs). In response to DSBs, the expression levels of LAP1 and TRF2 were significantly reduced. The phosphorylation of Histone 2A family member (γ-H2AX) that is considered the hallmark of DSBs was also evaluated. Upon DNA damage, LAP1 not only co-localizes with γ-H2AX in some specific points near nuclear envelope (NE) and nucleus, but also with TRF2 in the nuclear periphery. Moreover, LAP1 and TRF2 have been reported to be crucial for cell cycle progression. Therefore, we decided to pursued this issue. When the NE is reassembled, the complex is located mainly in specific regions of the NE, evidencing that TRF2 allows the attachment of chromosomes to NE membrane in somatic cells. In conclusion, our results are of paramount importance since novel functional insights regarding the novel LAP1:TRF2 complex were achieved particularly related with DNA damage response and cell cycle progression.<br>Proteína 1 associada com a lâmina (LAP1) é uma proteína integral da membrana do tipo II localizada na membrana nuclear interna (INM). O papel da LAP1 não é inteiramente sabido, no entanto esta proteína tem sido associada a algumas funções celulares devido às suas interações com as lâminas, proteína fosfatase 1 (PP1), emerina e torsinA. Além disso, novos putativos interactores da LAP1 estão a surgir. Um recente estudo do nosso grupo permitiu a identificação de vários novos putativos interactores da LAP1 envolvidos na sinalização dos telómeros e em respostas a danos no DNA, nomeadamente a mutação da ataxia telangiectasia (ATM), fator 2 de ligação às repetições teloméricas (TRF2), proteína 1 ativadora repressora (RAP1), fator homólogo 1 de interação com a RAP1 (RIF1), proteína 1 do checkpoint do fuso mitótico (MAD2L1) e a proteína de ligação à proteína 1 do checkpoint do fuso mitótico (MAD2L1BP). As interações proteína-proteína são cruciais no estudo das vias de sinalização. Neste estudo, a TRF2 foi identificada como uma nova proteína interatora da LAP1 utilizando tanto co-immunoprecipitação como metodologias baseadas em espectrometria de massa. Para determinar a relevância funcional do novo complexo LAP1:TRF2, células HeLa foram submetidas a danos no DNA através do peróxido de hidrogénio (H202), nomeadamente a quebras de DNA de cadeia dupla (DSBs). Em resposta a DSBs, os níveis de expressão da LAP1 e da TRF2 estavam significativamente reduzidos. A fosforilação do membro da família da histona 2A (γ-H2AX) que é considerado um biomarcador de DSBs foi também avaliada. Em resposta a danos no DNA, a LAP1 não só co-localiza com a γ-H2AX em alguns pontos específicos perto do invólucro nuclear (EN) e núcleo, mas também com TRF2 na periferia nuclear. Além disso, a LAP1 e a TRF2 têm sido reportadas como proteínas cruciais na progressão do ciclo celular. Por isso, decidimos prosseguir com esta questão. Quando o EN é remontado, o complexo está localizado principalmente em regiões especificas do EN, evidenciado que a TRF2 permite a ligação dos cromossomas à membrana do NE em células somáticas. Como conclusão, os nossos resultados são de uma importância suprema, uma vez que novas descobertas funcionais relativas ao novo complexo LAP1:TRF2 foram alcançadas, particularmente relacionadas com respostas a danos no DNA e progressão do ciclo celular.
46
Rodríguez, Solovey Leisa Natacha. "IDENTIFICATION OF TARGETS AND AUXILIARY PROTEINS OF PYR/PYL/RCAR ABA RECEPTORS: PROTEIN PHOSPHATASES TYPE 2C (PP2Cs) AND C2-DOMAIN ABA-RELATED PROTEINS (CARs)." Doctoral thesis, Universitat Politècnica de València, 2015. http://hdl.handle.net/10251/58862.
Full textAbstract:
[EN] ABSTRACT
Abscisic acid (ABA) signaling plays a critical role in regulating root growth and root system architecture. ABA-mediated growth promotion and root tropic response under water stress are key responses for plant survival under limiting water conditions. In this work, we have explored the role of Arabidopsis (Arabidopsis thaliana) PYR/PYL/RCAR receptors (PYRABACTIN RESISTANCE1 (PYR1)/PYR1 LIKE (PYL)/REGULATORY COMPONENTS OF ABA RECEPTORS) for root ABA signaling. As a result, we discovered that PYL8 plays a nonredundant role for the regulation of root ABA sensitivity. Unexpectedly, given the multigenic nature and partial functional redundancy observed in the PYR/PYL family, the single pyl8 mutant showed reduced sensitivity to ABA-mediated root growth inhibition. This effect was due to the lack of PYL8-mediated inhibition of several clade A phosphatases type 2C (PP2Cs), since PYL8 interacted in vivo with at least five PP2Cs, namely HYPERSENSITIVE TO ABA1 (HAB1), HAB2, ABAINSENSITIVE1 (ABI1), ABI2, and PP2CA/ABA-HYPERSENSITIVE GERMINATION3 as revealed by tandem affinity purification and mass spectrometry proteomic approaches.
Membrane-delimited abscisic acid (ABA) signal transduction plays a critical role in early ABA signaling, but the molecular mechanisms linking core signaling components to the plasma membrane are unclear. We show that transient calciumdependent interactions of PYR/PYL/RCAR ABA receptors with membranes are mediated through a 10-member family of C2-domain ABA-related (CAR) proteins in Arabidopsis thaliana. Specifically, we found that PYL4 interacted in an ABA-independent manner with CAR1 in both the plasma membrane and nucleus of plant cells. CAR1 belongs to a plant-specific gene family encoding CAR1 to CAR10 proteins, and bimolecular fluorescence complementation and coimmunoprecipitation assays showed that PYL4-CAR1 as well as other PYR/PYL-CAR pairs interacted in plant cells. The crystal structure of CAR4 was solved, which revealed that, in addition to a classical calcium-dependent lipid binding C2 domain, a specific CAR signature is likely responsible for the interaction with PYR/PYL/RCAR receptors and their recruitment to phospholipid vesicles. This interaction is relevant for PYR/PYL/RCAR function and ABA signaling, since different car triple mutants affected in CAR1, CAR4, CAR5, and CAR9 genes showed reduced sensitivity to ABA in seedling establishment and root growth assays. In summary, we identified PYR/PYL/RCAR-interacting partners that mediate a transient Ca2+-dependent interaction with phospholipid vesicles, which affects PYR/PYL/RCAR subcellular localization and positively regulates ABA signaling.<br>[ES] RESUMEN
La señalización por la hormona vegetal ácido abscísico (ABA) desempeña un papel crítico en la regulación del crecimiento de la raíz y en la arquitectura del sistema radical. La promoción de crecimiento de la raíz en condiciones de estrés hídrico mediada por ABA es clave para la supervivencia de las plantas bajo condiciones limitantes de agua. En este trabajo, hemos explorado el papel de los receptores PYR/PYL/RCAR (PYRABACTIN RESISTANCE1 (PYR1)/PYR1 LIKE (PYL)/ REGULATORY COMPONENTS OF ABA RECEPTORS) de Arabidopsis (Arabidopsis thaliana) en la ruta de señalización de ABA en raíz. Así, hemos descubierto que el receptor de ABA PYL8 juega un papel no redundante en la regulación de la percepción de ABA en raíz. Inesperadamente, dada la naturaleza multigénica y la redundancia funcional parcial observada en la familia PYR/PYL/RCAR, el mutante pyl8 fue el único mutante sencillo de pérdida de función de los receptores PYR/PYL/RCAR que mostraba una sensibilidad reducida a la inhibición del crecimiento mediada por ABA en raíz. Este efecto se debe a la falta de inhibición mediada por PYL8 de varias fosfatasas del grupo A tipo 2C (PP2Cs), ya que PYL8 es capaz de interactuar in vivo con al menos cinco PP2Cs, denominadas HYPERSENSITIVE TO ABA1 (HAB1), HAB2, ABAINSENSITIVE1 (ABI1), ABI2, and PP2CA/ABA-HYPERSENSITIVE GERMINATION3 según lo han revelado la purificación por afinidad en tándem (TAP por sus siglas en inglés) y estudios proteómicos de espectrometría de masas.
La transducción de la señal del ABA localizada en la membrana plasmática celular
juega un papel crucial en los pasos iniciales de la señalización de la fitohormona, pero los mecanismos moleculares que unen los componentes básicos de la señalización y la membrana plasmática no están claros. Estudiando las interacciones de los receptores del ABA PYR/PYL/RCAR con la membrana plasmática hemos encontrado que éstos pueden interaccionar transitoriamente con ella de forma dependiente de calcio gracias a una familia de proteínas con dominios C2 relacionadas con la ruta de señalización de ABA (denominadas C2-domain ABA-related (CAR) proteins). Específicamente, se encontró que PYL4 interacciona de manera independiente de ABA con CAR1 tanto en la membrana plasmática como en el núcleo de las células vegetales. La proteína CAR1 pertenece a una familia multigénica constituida por 10 miembros en Arabidopsis thaliana, desde CAR1 hasta CAR10, y que solo se encuentra en plantas. Los ensayos de complementación bi-molecular de fluorescencia y de co-immunoprecipitación confirmaron la interacción en células vegetales tanto de PYL4-CAR1 como de otras parejas de PYR/PYL-CAR. La cristalización de la proteína CAR4 reveló que, además de un dominio C2 clásico de unión a lípidos dependiente de calcio, las proteínas de la familia CAR presentan un dominio específico que probablemente es responsable de la interacción con los receptores PYR/PYL/RCAR y de su posterior reclutamiento a las vesículas de fosfolípidos. Esta interacción es relevante para la función de los receptores PYR/PYL/RCAR en la señalización del ABA, ya que diferentes mutantes triples car de pérdida de función, que tienen afectados los genes CAR1, CAR4, CAR5, y CAR9, demostraron una reducción de la sensibilidad al ABA en ensayos de establecimiento de plántula y crecimiento de la raíz. En resumen, hemos identificado nueva familia de proteínas que son capaces mediar las interacciones transitorias dependientes de Ca2+ con vesículas de fosfolípidos, lo que a su vez afecta localización de PYR/PYL/RCAR y regula positivamente la señalización de ABA.<br>[CAT] RESUM
La senyalització per l'hormona vegetal àcid abcíssic (ABA) exerceix un paper crític en la regulació del creixement de l'arrel i també en l'arquitectura del sistema radical. La promoció del creixement de l'arrel en condicions d'estrés hídric, regulada per ABA és clau per la supervivència de les plantes sota condicions limitants d'aigua. Amb aquest treball, hem investigat el paper dels receptors PYR/PYL/RCAR (PYRABACTIN RESISTANCE1 (PYR1)/PYR1 LIKE (PYL)/ REGULATORY COMPONENTS OF ABA RECEPTORS) d'Arabidopsis (Arabidopsis thaliana) en el camí de senyalització d'ABA en arrel. Així, hem descobert que el receptor d'ABA PYL8 exerceix un paper no redundant en la regulació de la percepció d'ABA en arrel. Inesperadament, donada la naturalesa multigènica i la redundància funcional parcial que s'observa en la família PYR/PYL/RCAR, el mutant pyl8 va ser l'únic mutant senzill de pèrdua de funció dels receptors PYR/PYL/RCAR que mostrava una sensibilitat reduïda a la inhibició del creixement mitjançada per l'ABA en l'arrel. Doncs aquest efecte es deu a la falta d'inhibició regulada per PYL8 de diverses fosfatases del grup A tipus 2C (PP2Cs), ja que PYL8 té la capacitat d'interactuar in vivo almenys amb cinc PP2Cs, anomenades HYPERSENSITIVE TO ABA1 (HAB1), HAB2, ABAINSENSITIVE1 (ABI1), ABI2, and PP2CA/ABAHYPERSENSITIVE GERMINATION3 segons ho han revelat per una banda la purificació per afinitat en tàndem (TAP són les seues sigles en anglés) i per altra banda, estudis proteòmics d'espectrometria de masses.
Pel que fa a la transducció del senyal del l'ABA, la qual es localitza en la membrana plasmàtica cel¿lular, juga un paper molt important en els primers instants de la senyalització de la fitohormona, no obstant això els mecanismes moleculars que uneixen els components bàsics d'aquesta senyalització amb la membrana plasmàtica, no es troben del tot clars. Per tant, s'han estudiat les interaccions que tenen els receptors del ABA PYR/PYL/RCAR amb la membrana plasmàtica, i hem trobat que aquests tenen la capacitat d'interaccionar transitòriament amb la membrana de forma dependent al calci, gràcies a una família de proteïnes amb domini C2, les quals es troben relacionades amb la ruta de senyalització d'ABA(anomenades C2domain ABArelated (CAR) proteins).Específicament, es va trobar que PYL4 interacciona d'una manera independent al ABA amb CAR1, tant en la membrana plasmàtica, com en el nucli de les cèl¿lules vegetals. La proteïna CAR1 pertany a la família multigènica constituïda per 10 components en Arabidopsis thaliana, des de CAR1 fins CAR10, que tan sols es troba en plantes. Els assajos de complementació bimolecular de fluorescència i de co-immunoprecipitació, van confirmar la interacció en cèl¿lules vegetals, tant de PYL4CAR1 com d'altres parelles de PYR/PYL-CAR. La cristal¿lització de la proteïna CAR4 va revelar que, a més d'un domini C2 clàssic de unió a lípids dependent del calci, les proteïnes de la família CAR presenten un domini PYR/PYL/RCAR, i del seu posterior reclutament a les vesícules fosfolipídiques. Doncs, aquesta interacció és rellevant en la funció dels receptors PYR/PYL/RCAR, ja que participa en la senyalització del l'ABA. Aquesta interacció es clau per a la funció dels receptors, ja que diferents mutants triples car de pèrdua de funció, els quals posseïxen afectats els gens CAR1, CAR4, CAR5 i CAR9, van mostrar una reducció de la sensibilitat a l'ABA en assajos d'establiment de plàntula i creixement de l'arrel. En conclusió, hem identificat una nova família de proteïnes amb la capacitat d'organitzar les interaccions transitòries dependents del calci amb vesícules de fosfolípids, fet que al seu torn afecta la localització de PYR/PYL/RCAR i regula positivament la senyalització d'ABA.<br>Rodríguez Solovey, LN. (2015). IDENTIFICATION OF TARGETS AND AUXILIARY PROTEINS OF PYR/PYL/RCAR ABA RECEPTORS: PROTEIN PHOSPHATASES TYPE 2C (PP2Cs) AND C2-DOMAIN ABA-RELATED PROTEINS (CARs) [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/58862<br>TESIS
47
Zabihi, Sheller. "Fetal Outcome in Experimental Diabetic Pregnancy." Doctoral thesis, Uppsala University, Department of Medical Cell Biology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8739.
Full textAbstract:
<p>Women with pregestational diabetes have a 2-5 fold increased risk of giving birth to malformed babies compared with non-diabetic women. Diabetes-induced oxidative stress in maternal and embryonic tissues has been implicated in the teratogenic process. The malformations are likely to be induced before the seventh week of pregnancy, when the yolk sac is partly responsible for the transfer of metabolites to the embryo, and the uterine blood flow to the implantation site determines the net amount of nutrients available to the conceptus. We aimed to evaluate the effect on embryogenesis caused by a diabetes-induced disturbance in yolk sac morphology, uterine blood flow or altered maternal antioxidative status in conjunction with a varied severity of the maternal diabetic state.</p><p>We investigated to which extent maternal diabetes with or without folic acid (FA) supplementation affects mRNA levels and protein distribution of ROS scavenging enzymes (SOD, CAT, GPX), vascular endothelial growth factor-A (Vegf-A), folate binding protein-1 (Folbp-1), and apoptosis associated proteins (Bax, Bcl-2, Caspase-3) in the yolk sacs of rat embryos on gestational days 10 and 11. We found that maternal diabetes impairs, and that FA supplementation restores, yolk sac vessel morphology, and that maternal diabetes is associated with increased apoptotic rate in embryos and yolk sacs, as well as impaired SOD gene expression. We assessed uterine blood flow with a laser-Doppler-flow-meter and found increased blood flow to implantation sites of diabetic rats compared with controls. Furthermore, resorbed and malformed offspring showed increased and decreased blood flow to their implantation sites, respectively. In mice with genetically altered CuZnSOD levels, maternal diabetes increased embryonic dysmorphogenesis irrespective of CuZnSOD expression. We thus found the maternal diabetic state to be a major determinant of diabetic embryopathy and that the CuZnSOD status exerts a partial protection for the embryo in diabetic pregnancy. </p>
48
Tran, Anh-Nhi. "A Genetic Survey of the Pathogenic Parasite Trypanosoma cruzi." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3425.
Full text
49
Tan, Kah Poh. "Nuclear Factor (Erythroid 2-like) Factor 2 (Nrf2) as Cellular Protector in Bile Acid and Retinoid Toxicities." Thesis, 2008. http://hdl.handle.net/1807/17287.
Full textAbstract:
Exposure to toxic bile acids (BA) and retinoic acids (RA) is implicated in toxicities related to excessive oxidative stress. This thesis examined roles and mechanisms of the oxidative stress-responsive nuclear factor (erythroid 2-like) factor 2 (Nrf2) in adaptive cell defense against BA and RA toxicities. Using liver cells and mouse models, many antioxidant proteins known to be Nrf2 target genes, particularly the rate-limiting enzyme for glutathione (GSH) biosynthesis, i.e., glutamate-cysteine ligase subunits (GCLM/GCLC), were induced by BA [lithocholic acid (LCA)] or RA (all-trans, 9-cis and 13-cis) treatment. Evidence for increased Nrf2 transactivation by LCA and all-trans-RA was exemplified in HepG2 by: (1) reduced constitutive and inducible expression of GCLM/GCLC upon Nrf2 silencing via small-interfering RNA; (2) increased inducible expression of GCLM/GCLC genes by Nrf2 overexpression, but overexpression of dominant-negative Nrf2 decreased it; (3) increased nuclear accumulation of Nrf2 as signature event of receptor activation; (4) enhanced Nrf2-dependent antioxidant-response-element (ARE) reporter activity as indicative of increased Nrf2 transactivation; and (5) increased Nrf2 occupancy to AREs of GCLM and GCLC. Additionally, in BA-treated HepG2 cells, we observed concomitant increases of many ATP-binding cassette (ABC) transporters (MRPs 1-5, MDR1 and BCRP) in parallel with increased cellular efflux. Nrf2 silencing in HepG2 cells decreased constitutive and inducible expression of MRP2, MRP3 and ABCG2. However, Nrf2-silenced mouse hepatoma cells, Hepa1c1c7, and Nrf2-/- mice had decreased constitutive and/or inducible expression of Mrps 1-4, suggesting species differences in Nrf2-dependent regulation of hepatic ABC transporters. Protection by Nrf2 against BA and RA toxicities was confirmed by observations that Nrf2 silencing increased cell susceptibility to BA- and RA-induced cell death. Moreover, Nrf2-/- mice suffered more severe liver injury than the wildtype. Increased GSH and efflux activity following increased GCLM/GCLC and ABC transporters, respectively, can mitigate LCA toxicity. Activation of MEK1-ERK1/2 MAPK was shown to primarily mediate Nrf2 transactivation and LCA-induced expression of antioxidant proteins and Nrf2-dependent and -independent ABC transporters. In conclusion, Nrf2 activation by BA and RA led to coordinated induction of antioxidant and ABC proteins, thereby counteracting resultant oxidative cytotoxicity. The potential of targeting Nrf2 in management of BA and RA toxicities merits further investigation.
50
Reza, Faisal. "Computational Molecular Engineering Nucleic Acid Binding Proteins and Enzymes." Diss., 2010. http://hdl.handle.net/10161/2278.
Full textAbstract:
<p>Interactions between nucleic acid substrates and the proteins and enzymes that bind and catalyze them are ubiquitous and essential for reading, writing, replicating, repairing, and regulating the genomic code by the proteomic machinery. In this dissertation, computational molecular engineering furthered the elucidation of spatial-temporal interactions of natural nucleic acid binding proteins and enzymes and the creation of synthetic counterparts with structure-function interactions at predictive proficiency. We examined spatial-temporal interactions to study how natural proteins can process signals and substrates. The signals, propagated by spatial interactions between genes and proteins, can encode and decode information in the temporal domain. Natural proteins evolved through facilitating signaling, limiting crosstalk, and overcoming noise locally and globally. Findings indicate that fidelity and speed of frequency signal transmission in cellular noise was coordinated by a critical frequency, beyond which interactions may degrade or fail. The substrates, bound to their corresponding proteins, present structural information that is precisely recognized and acted upon in the spatial domain. Natural proteins evolved by coordinating substrate features with their own. Findings highlight the importance of accurate structural modeling. We explored structure-function interactions to study how synthetic proteins can complex with substrates. These complexes, composed of nucleic acid containing substrates and amino acid containing enzymes, can recognize and catalyze information in the spatial and temporal domains. Natural proteins evolved by balancing stability, solubility, substrate affinity, specificity, and catalytic activity. Accurate computational modeling of mutants with desirable properties for nucleic acids while maintaining such balances extended molecular redesign approaches. Findings demonstrate that binding and catalyzing proteins redesigned by single-conformation and multiple-conformation approaches maintained this balance to function, often as well as or better than those found in nature. We enabled access to computational molecular engineering of these interactions through open-source practices. We examined the applications and issues of engineering nucleic acid binding proteins and enzymes for nanotechnology, therapeutics, and in the ethical, legal, and social dimensions. Findings suggest that these access and applications can make engineering biology more widely adopted, easier, more effective, and safer.</p><br>Dissertation