To see the other types of publications on this topic, follow the link: Ticks salivary glands.

Dissertations / Theses on the topic 'Ticks salivary glands'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 21 dissertations / theses for your research on the topic 'Ticks salivary glands.'

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

Liu, Xiangye. "Identification of Ixodes ricinus female salivary glands factors involved in Bartonella henselae transmission." Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST1066/document.

Full text
Abstract:
Aujourd'hui, l'émergence ou la réémergence de maladies transmises par les tiques (TBDs) devient un problème majeur. En raison des problèmes générés par l'utilisation des acaricides (pollution, résistance), il est donc urgent d'identifier de nouvelles approches pour contrôler les populations de tiques. Parmi ces stratégies, la vaccination visant des molécules conservées chez les tiques et impliquées dans leur capacité vectorielle, sont devenues particulièrement attractives. En conséquence, l'identification de cibles antigéniques appropriées est un défi majeur pour la mise en œuvre de ces stratégies de contrôle des tiques et des TBDs. Dans le présent travail, l'objectif principal est d'élucider les interactions moléculaires entre I. ricinus et B. henselae, afin d'identifier des molécules qui pourraient représenter des cibles vaccinales contre les tiques et les agents pathogènes qu'elles transmettent. Dans ce but, nous avons identifié, par séquençage à haut débit, des transcrits d'Ixodes ricinus différentiellement exprimés au niveau des glandes salivaires de la tique en réponse à une infection par B. henselae. Dans un second temps, l'implication d'un de ces transcrits surexprimés lors de l'infection dans la transmission de B. henselae, a été évaluée. Enfin, et en premier lieu, nous avons validé l'utilisation de la technique de gorgement artificiel sur membrane pour infecter I. ricinus par B. henselae et évalué l'impact de différents paramètres sur le gorgement des tiques. Les résultats ont montré que la technique de gorgement sur membrane est bien adaptée à l'infection d'I. ricinus par B. henselae en laboratoire, et que la proportion et le poids des tiques gorgées sont diminués lors de l'infection du sang par la bactérie Le séquençage en 454 des glandes salivaires de tiques a généré une banque de référence contenant 24, 539 transcrits, et la comparaison des glandes salivaires d'I. ricinus infectés et non-infectés par B. henselae a montré que 839 et 517 transcrits étaient respectivement significativement surexprimés et sous-exprimés en réponse à l'infection par des bactéries. Parmi les gènes de fonction connue, 161 transcrits correspondent à 9 familles déjà identifiées, quand les autres correspondent à des gènes de fonction inconnue. L'extinction par RNA interférence du gène le plus surexprimé, IrSPI qui appartient à la famille des inhibiteurs de sérine protéase BPTI/Kunitz, a entraîné une réduction de la taille du repas sanguin prit par les tiques (et donc sa descendance) ainsi que du niveau d'infection au niveau des glandes salivaires. En conclusion, cette étude a démontré que la technique de gorgement artificiel des tiques sur membrane est un outil puissant pour étudier les interactions entre les tiques et les agents pathogènes qu'elles transmettent comme B. henselae. Ce travail apporte aussi une nette avancée en termes de données génétiques sur I. ricinus (dont le génome n'est pas séquencé) et sur les interactions moléculaires entre une bactérie et son vecteur. Enfin, ce travail a permis la mise en évidence d'une molécule représentant un candidat vaccinal très prometteur à la fois pour diminuer la population de tiques et lutter contre les agents pathogènes qu'elles transmettent. Dans le futur, et en fonction de la confirmation du rôle des gènes identifiés ici dans la transmission bactérienne, de nombreux candidats vaccins pourront ainsi être évalués, ouvrant alors de nouvelles perspectives dans la lutte contre les tiques et les maladies dues aux agents qu'elles transmettent
Ticks are obligate blood-feeding ectoparasites of many hosts including mammals, birds and reptiles. After mosquitoes, they are the most important vectors worldwide, and are able to transmit the highest variety of pathogens including virus, bacteria and parasites. Ixodes ricinus (Acari: Ixodidae), the most common tick species in Europe, is a three-life stage hard tick. It is frequently associated with bites in humans, and transmits several pathogens, including Tick-Borne Encephalitis, Babesia spp., Borrellia spp., Anaplasma spp., and to a lesser extent Bartonella spp. Bartonella spp. are facultative intracellular bacteria associated with a number of emerging diseases in humans and animals. It has been demonstrated that I. ricinus is a competent vector for B. henselae that causes cat scratch disease as well as being increasingly associated with a number of other syndromes, particularly ocular infections and endocarditis. Recently, emergence or re-emergence of tick-borne diseases (TBDs) is increasingly becoming a problem. Indeed, and because of the limited success and disadvantages of controlling TBDs via acaricides, new approaches are urgently needed. Therefore, vaccine strategies that target conserved components of ticks that play roles in vector infestation and vector capacity have become particularly attractive. Accordingly, the identification of suitable antigenic targets is a major challenge for the implementation of tick and TBDs control strategies. In the present work, the main objective is to elucidate molecular interactions between I. ricinus and B. henselae in order to identify some targets that may be used as vaccines against ticks and tick-borne pathogens. Two principal points are focused on: primarily, to identify I. ricinus salivary gland differentially expressed transcripts in response to B. henselae infection with next generation sequencing techniques (454 pyrosequencing and HiSeq 2000); secondly, to validate the implication of one of these transcripts in the transmission of B. henselae. For that purpose, and at first, we validated artificial membrane feeding technique for ticks infection by B. henselae and evaluated the impact of several parameters on tick feeding. Results showed that membrane feeding technique is a suitable method to infect I. ricinus with B. henselae and that the proportion and weight of engorged ticks are decreased by B. henselae infection of the blood meal. Transcriptional analysis of the tick salivary glands generated a reference databank containing 24,539 transcripts, and the comparison of B. henselae-infected and non-infected I. ricinus female salivary glands showed that 839 and 517 transcripts were significantly up- and down-regulated in response to bacteria infection, respectively. Among them, 161 transcripts corresponded to 9 groups of ticks salivary gland gene families already described, when the other ones corresponded to genes of unknown function. Silencing the most up-regulated gene IrSPI, which belongs to BPTI/Kunitz family of serine protease inhibitor, resulted in reduction of tick feeding and bacteria load in tick salivary gland. In conclusion, this work demonstrated that artificial-membrane feeding technique is a powerful tool for investigating the interactions between tick and tick-borne pathogens as B. henselae. It also increases the available genomic information for I. ricinus and the knowledge to improve our understanding of the molecular interaction between tick and tick-borne pathogens. At last, it provides a potential vaccine candidate to control tick-borne diseases. In the future, and depending of differentially expressed genes' role confirmation, more and more vaccine candidate will be provided by this work, and the strategy of controlling tick and tick-borne disease will come to a new stage
APA, Harvard, Vancouver, ISO, and other styles
2

Kim, Donghun. "Molecular physiology of tick salivary secretion and transcriptomics of tick in interaction with tick-borne pathogen." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32691.

Full text
Abstract:
Doctor of Philosophy
Entomology
Yoonseong Park
Tick salivary secretion is crucial for survival and for successful feeding. Tick saliva includes excretory water/ions and bioactive components for compromising the hosts' immune responses, and provides a direct route for pathogen transmission. Control of the tick salivation involves autocrine/paracrine dopamine, the most potent stimulator of tick salivation. Our research group reported the presence of two dopamine receptors in the salivary glands of the blacklegged tick (Ixodes scapularis): dopamine receptor (D1) and invertebrate specific D1-like dopamine receptor (InvD1L). Dopamine-induced salivary secretion was orchestrated by two distinct physiological roles via activation of the two dopamine receptors (Chapter 2). Low concentration of dopamine activated D1 receptor on epithelial cells of salivary gland acini leading inward fluid transport. High concentration of dopamine activated InvD1L receptors on axonal projections innervating myoepithelial cells modulating pumping/gating actions for emptying luminal saliva into the main duct. Thus, ticks coordinated salivary secretion with duo dopamine receptors. Dopamine-mediated saliva production involves an important downstream component, Na/K-ATPase (Chapter 3). Na/K-ATPase was found in the epithelial cells of all types of acini. However, Na/K-ATPase had two different functions in salivary secretion in different acini: 1) dopamine-mediated production of primary saliva in distally located salivary gland acini type-2/- 3, and 2) dopamine-independent resorption in proximally located salivary gland acini type-1. Type-1 acini were also found to function in direct water absorption of off-host ticks, which could be a potential route for delivery of acaricides. Chapter 4 investigated the comparative transcriptomics of the lone star tick underlying the processes of pathogen acquisition. Differential expression analyses in pathogen-exposed ticks revealed a number of transcripts that are important in the tick-pathogen interaction. These included genes for tick immunity against pathogen and for modulation of tick physiology facilitating a pathogen’s invasion and proliferation. My study expanded the understanding of physiological mechanisms controlling tick salivation. In addition, transcriptomics of ticks in interaction with pathogen identified several genes that are relevant in vector/pathogen interactions. The knowledge obtained in my study will facilitate to the development of novel methods for the disruption of tick feeding and pathogen transmission.
APA, Harvard, Vancouver, ISO, and other styles
3

Maritz-Olivier, Christine. "The Mechanisms regulating exocytosis of the salivary glands of the soft tick, Ornithodorus savignyi." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-02152006-122509.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Selim, Mohamed E. "Tick-host interactions : evaluation of resistance, salivary gland antigens, and DNA vaccination /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488193272067399.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Mans, Ben J. (Barend Johannes). "Functional perspectives on the evolution of argasid tick salivary gland protein superfamilies." Thesis, University of Pretoria, 2002. http://hdl.handle.net/2263/28635.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Delroux, Karine. "Cloning of genes expressed in the salivary glands during feeding of the tick Amblyomma variegatum." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/29727.

Full text
Abstract:
The purpose of this study is to characterise molecules that are secreted in tick salivary glands. A cDNA library of salivary glands was constructed in a lambda phage. Immunoscreening was carried out with a) a hyperimmune antiserum obtained from rabbit immunised with salivary gland extract of unfed A variegatum, b) an antiserum from a rabbit exposed to feeding A variegatum; c) an antiserum from calf repeatedly exposed to feeding A variegatum. All antisera recognised proteins of salivary glands extracts on Western blot analysis, but none detected recombinant salivary gland proteins from the cDNA library. A random selection of cDNA clones were sequenced and compared with those from the Amblyomma variegatum Gene Index (AvGI) and the GenBank of non-redundant sequences database (NCBI). Several clones displayed sequence identity with already known sequences from other tick species. One clone displayed 31% identity with a consensus sequence of the AvGI EST, which shared 28% identity with a 36kDa immunosuppressant molecule isolated from Dermacentor andersoni. Screening of the cDNA library, using the Signal Sequence Trap technique, identified a clone with 99% identity with a glycine rich protein from the AvGI database. This gene was designated FLAv41E and had a molecular weight of 30.9kDa. Reverse transcription PCR (polymerase chain reaction) amplification of FLAv41E gene revealed that it is expressed in the salivary glands of A variegatum female from day 3 to 10 of feeding. Its secondary structure revealed domain similarities with a 29kDa cement protein characterised in Haemaphysalis longicornis ticks. The recombinant FLAv41E protein was expressed in insect cells using a baculovirus system. FLAv41E appears to be a cement protein.
APA, Harvard, Vancouver, ISO, and other styles
7

Jaworski, Deborah Carol. "Molecular aspects of early-expressed ixodid tick salivary gland antigens with emphasis on host response to tick feeding /." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487694702782423.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Lees, Sarah Alexandra. "Analysis of the Brown Dog Tick, Rhipicephalus sanguineus, salivary gland transcriptome for potential drug targets." Thesis, University of Aberdeen, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439965.

Full text
Abstract:
The dopamine receptor is critical in fluid secretion from tick salivary glands and, as such, was perceived as a potential drug target.  Homology cloning was employed to isolate a dopamine receptor from R. sanguineus salivary glands.  A dopamine receptor was successfully cloned from locust salivary glands although not from R. sanguineus salivary glands. A cDNA library was constructed from feeding female R. sanguineus salivary glands and random mass sequencing of 1440 clones was performed. Sequences were identified from database searches and classified according to gene ontology.  Several enzymes were identified as potential drug targets and a glutathione S-transferase (GST) was chosen for further study.  The dopamine receptor was not identified, as were no other G protein-coupled receptors. A mu class GST from R. sanguineus salivary glands was expressed as a recombinant protein in E. coli and was found to have differences when compared to other tick GSTs, namely low catalytic activity with a model substrate.  Preliminary studies suggested that the GST is not involved in prostaglandin synthesis and the GST bound haematin with high affinity.  Of several tissues investigated within female ticks, the GST mRNA was only expressed in the salivary glands and only in glands from feeding female ticks indicating a potential role in blood feeding. Two approaches were employed to identify drug targets in R. sanguineus salivary glands.  It is concluded that whilst random mass sequencing of a cDNA library yields many potential targets, because of the nature of the salivary gland tissue with high repetition of mitochondrial and secretory protein RNA, homology cloning would be the recommended approach for scientific, low abundance targets.
APA, Harvard, Vancouver, ISO, and other styles
9

Mao, Helen. "Characterization of the ecdysteroid receptor in the salivary gland of the ixodid tick, Amblyomma hebraeum Koch." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ34807.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Fain-Thornton, Jennifer M. "Isolation, expression, purification and characterization of full-length calreticulin from the salivary glands of the ixodid tick, Amblyomma americanum /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487948158627036.

Full text
APA, Harvard, Vancouver, ISO, and other styles
11

Mahlaku, Matsatsane Martha. "Biochemical investigations into the proteolytic activities in salivary glands of the tick, Ornithodoros savignyi." Diss., 2003. http://hdl.handle.net/2263/25727.

Full text
Abstract:
The saliva of hematophagous ectoparasites contains a cocktail of vasodilators, anticoagulants and immunosuppressors that maintain blood in a liquid state at the site of the lesion and evade the host's defense mechanisms in suppressing the immune response. Since ticks have evolved to utilize mammals as a source of food, our understanding of the tick material, especially the salivary glands will enhance the control of tick infestation and allow the exploitation of the tick's natural resources. SGE protease activity was determined by measuring the degradation of azocasein. Proteolytic activity was found in the pH range of 3 to 11 with the highest activity at pH 9 followed by pH 7. At pH 3-5 the activity was mainly due to aspartic proteases, whereas at pH 7-9 the activity was due to the action of metallo- and serine proteases. At pH 11, the activity was mainly ascribed to metallo- and aspartic proteinase activity The fibrinogenolytic activity was determined by incubating human fibrinogen in the presence of SGE and monitoring the fibrinogen degradation by SDS-PAGE. SGE degraded the Au-chain of fibrinogen within 2 hours of incubation and even after 24 hours incubation there was no hydrolysis of the Bβ and γ-chains of fibrinogen. Characterization of the fibrinogenolytic activity revealed that metalloprotease activity was present over pH range of 3-9 and at pH 3-5, the cysteine proteases were active. No serine protease activity was found under similar experimental conditions. CE-HPLC separation of the SGE revealed three regions of proteolytic activity. Further characterization of the activity containing fractions using protease inhibitors at various pH values showed that the activity associated with region A is mainly due to the presence of aspartic and cysteine proteases in the lower pH range (< 5). Region B was mainly due to the activity of the metallo- and serine proteases, while the activity in region C was mainly due to the metalloproteinases which were more active in the higher pH range (> 9). CE-HPLC separation of SGE resulted in three regions exhibiting fibrinogenolytic activity at pH 7-9. In region A all four enzyme classes were found while in regions B and C, serine, cysteine and metalloproteinases were found to be responsible for the activity. Region A was further purified on the HIC-column and activity eluted in several peaks which after individual application on SE-HPLC column had similar retention times. The pooled samples were analyzed for purity using C5 RP-HPLC and reducing tricine SDS-PAGE and three bands of relative molecular masses 15, 22 and 12 kDa, respectively were found. In an attempt to purify the proteins in region C, four individual CE-HPLC runs were combined and applied to a fibrinogen affinity column. Reducing SDS-PAGE analysis of bound material showed two bands of relative molecular masses of 31 and 39 kDa, respectively. CE-HPLC region C as well as the SGE control was found to disaggregate platelets aggregated by ADP, epinephrine, collagen as well as TRAP. No disaggregation was observed for the saline negative control. The disaggregation is most probably due to the hydrolysis of the fibrinogen cross-linking platelets by the metalloproteinase activity in region C. Understanding of the proteolytic activities present in the salivary gland and therefore identifying molecules crucial for tick feeding could aid in the development of experimental vaccines. Even though the fibrinogenolytic activity was not purified to homogeneity, this study has laid the groundwork for further experiments in this field.
Dissertation (MSc (Biochemistry))--University of Pretoria, 2006.
Biochemistry
unrestricted
APA, Harvard, Vancouver, ISO, and other styles
12

Tothová, Viktorie. "Hyaluronidáza ve slinách ovádů a klíšťat." Master's thesis, 2010. http://www.nusl.cz/ntk/nusl-295904.

Full text
Abstract:
6 1. Abstrakt Hyaluronidázy jsou významnou skupinou enzymů odpovědných za štěpení kyseliny hyaluronové, která je jednou z hlavních složek pojivové tkáně obratlovců. U většiny krevsajících členovců je tento enzym přítomen ve slinách a usnadňuje sání tím, že se podílí na průniku kůží a zvětšení potravní léze v místě bodnutí. Vzniklé fragmenty extracelulární matrix mohou navíc modulovat lokální imunitní odpověď hostitele a zvyšovat pravděpodobnost přenosu patogenů. V naší práci jsme se zaměřili na průkaz hyaluronidázové aktivity u klíštěte Ixodes ricinus (Acari: Ixodidae) a zástupců čtyř rodů ovádů (Diptera: Tabanidae). V slinných žlázách klíšťat se hyaluronidázovou aktivitu detekovat nepodařilo. Naopak, ve slinných žlázách ovádů jsme prokázali velmi silnou aktivitu u všech studovaných druhů a dále ji charakterizovali biochemickými a elektroforetickými metodami. Hyaluronidázy ovádů štěpí hyaluronan i chondroitin sulfát; enzymy jednotlivých druhů se mírně liší molekulovou hmotností, pH optimem a citlivostí k redukujícím podmínkám. Abstract (in English) Hyaluronidases are an important group of enzymes responsible for cleaving hyaluronic acid, which is a major component of the extracellular matrix of vertebrates. In bloodsucking arthropods these enzymes are frequently present in saliva. Salivary hyaluronidases...
APA, Harvard, Vancouver, ISO, and other styles
13

Genu, Siyamcela. "Salivary gland transcriptome of Rhipicephalus (Boophilus) microplus." Diss., 2018. http://hdl.handle.net/10500/24972.

Full text
Abstract:
The cattle tick, Rhipicephalus (Boophilus) microplus is a tick of veterinary and health importance globally, transmitting Babesia bovis and B. bigemina. Tick control is important and needed to prevent livestock diseases caused by tick-transmitted pathogens. Traditionally, tick control methods have resulted in development of acaricide-resistant ticks, environmental pollution and meat and milk contamination. Therefore, there is a need for alternative method and vaccines directed against tick feeding. The aim of this study was to identify proteins involved in tick feeding, tickhost-pathogen interactions and tick reproduction. Consequently, these will help in identification of antigens with the ultimate goal of developing anti-tick vaccines. R. (B.) microplus female ticks were collected at five different feeding stages. RNA was isolated from the salivary gland extracts (SGEs). The cDNA libraries were synthesized and sequenced with the Illumina MiSeq technology. Transcriptome data was analyzed with CLC Genomics Workbench, Trinity and Minia. The SGEs were also used to isolate the fractions: membrane, soluble and pellet protein for proteomic analysis. The proteomics data was analysed with Mascot, X!Tandem and Scaffold. Both the transcriptome and proteome analysis revealed the presence of major secretory protein families such as Kunitz, lipocalins, serpins, cement proteins and metalloproteases, while the majority of transcripts coded for housekeeping genes.
National Research Foundation (South Africa)
Life and Consumer Science
M. Sc. (Life Science)
APA, Harvard, Vancouver, ISO, and other styles
14

De, Castro Minique Hilda. "Sialotranscriptomics of the brown ear ticks, Rhipicephalus appendiculatus Neumann, 1901 and R. Zambeziensis Walker, Norval and Corwin, 1981, vectors of Corridor disease." Thesis, 2017. http://hdl.handle.net/10500/24735.

Full text
Abstract:
Text in English
Corridor disease is an economically important tick-borne disease of cattle in southern Africa. The disease is caused by Theileria parva and transmitted by the vectors, Rhipicephalus appendiculatus and R. zambeziensis. There is currently no vaccine to protect cattle against T. parva that is permitted in South Africa. To develop recombinant anti-tick vaccines against Corridor disease, comprehensive databases of genes expressed in the tick’s salivary glands are required. Therefore, in Chapters 2 and 3, mRNA from the salivary glands of R. appendiculatus and R. zambeziensis was sequenced and assembled using next generation sequencing technologies. Respectively, 12 761 and 13 584 non-redundant protein sequences were predicted from the sialotranscriptomes of R. appendiculatus and R. zambeziensis and uploaded to public sequence domains. This greatly expanded the number of sequences available for the two vectors, which will be invaluable resources for the selection of vaccine candidates in future. Further, in Chapter 3, differential gene expression analysis in R. zambeziensis revealed dynamic expression of secretory protein transcripts during feeding, suggestive of stringent transcriptional regulation of these proteins. Knowledge of these intricate expression profiles will further assist vaccine development in future. In Chapter 4, comparative sialotranscriptomic analyses were performed between R. appendiculatus and R. zambeziensis. The ticks have previously shown varying vector competence for T. parva and this chapter presents the search for correlates of this variance. Phylogenetic analyses were performed using these and other publically available tick transcriptomes, which indicated that R. appendiculatus and R. zambeziensis are closely related but distinct species. However, significant expression differences were observed between the two ticks, specifically of genes involved in tick immunity or pathogen transmission, signifying potential bioinformatic signatures of vector competence. Furthermore, nearly four thousand putative long non-coding RNAs (lncRNAs) were predicted in each of the two ticks. A large number of these showed differential expression and suggested a potential transcriptional regulatory function of lncRNA in tick blood feeding. LncRNAs are completely unexplored in ticks. Finally, in Chapter 5, concluding remarks are given on the potential impact the R. appendiculatus and R. zambeziensis sialotranscriptomes may have on future vaccine developments and some future research endeavours are discussed.
Life and Consumer Sciences
Ph. D. (Life Sciences)
APA, Harvard, Vancouver, ISO, and other styles
15

Maritz-Olivier, Christine. "The mechanisms regulating exocytosis of the salivary glands of the soft tick,Ornithodoros savignyi." Thesis, 2005. http://hdl.handle.net/2263/28838.

Full text
Abstract:
Numerous bioactive compounds are secreted from large dense core granules in tick salivary glands during feeding. Investigations into the signalling pathways regulating secretion indicated that they are similar for Argasidae (fast feeding ticks) and Ixodidae (slow-feeding ticks). In both cases, dopamine is the external signal that activates adenylyl cyclase, subsequently cyclic AMP levels are increased and Protein Kinase A (PKA) is activated, resulting in the phosphorylation of proteins. Secretion was also found to be highly calcium dependant. Firstly, it requires extracellular calcium (via a L-type voltage-gated calcium channel located on the plasma membrane) and secondly, intracellular calcium which is released presumably in response to IP3. In contrast to numerous exocrine cells, membrane depolarisation and elevation of the cAMP levels are not sufficient for inducing exocytosis from O. savignyi salivary glands. Pathways such as the activation of Phospholipase C, inositol-phosphate kinases, Na+K+-ATPases, as well as the disassembly of the actin barrier, have been shown to be essential. Finally, our research also indicated a need for the ATPase NSF, an intact microtubule network and an active cytosolic Phospholipase A2 for exocytosis. A model has been suggested, but a great deal of research is needed to elucidate all the mechanisms of regulated exocytosis. All secretory eukaryotic cells to date require SNARE proteins for fusion of granules with the plasma membrane, leading to the release of granular content. By means of Western blotting we identified the tick homologues of the SNAREs syntaxin, SNAP25 and VAMP, as well as the small GTPase Rab3a, all enriched within the membrane fraction. We also identified the SDS-resistant 20S complex, which forms during the docking of granules and is composed of the three SNARE proteins. Confocal microscopy of the SNARE proteins indicates SNAP25 and VAMP localize to the granule membranes, while syntaxin localises strictly to the plasma membrane. In order to isolate the tick SNARE homologues we exploited protein-protein interactions by means of the yeast two-hybrid system. Screening of an O. savignyi cDNA salivary gland library using rat brain a-SNAP as bait, we identified a transcript encoding a tick syntaxin homologue. It encoded a 126 residue protein which shares 14% identity and 40% similarity with human syntaxin 1. Furthermore, we were able to successfully model the identified protein onto the known crystal structure of human syntaxin 1 and indicate that it shares structural homology with helices 1, 2, 3 and the connecting two loop regions. Following screening of the library with a truncated syntaxin bait construct, two novel domains were identified in all the interacting clones. To date their identity remains unknown. Functional complementation in the syntaxin knockout yeast strain H603 with an O. savignyi cDNA library resulted in the identification of four novel transcripts, which suppressed the temperature sensitive phenotype. Two of these share homology with the N- and C-terminals of syntaxins respectively and were successfully modelled onto the human syntaxin 1 crystal structure. Finally, by exploiting the extensive SNARE binding properties of recombinant rat brain a-SNAP, we were able to isolate the O. savignyi SNAREs, i.e. syntaxin, SNAP25 and VAMP, using pull-down assays. These purified proteins will soon be subjected to amino acid sequencing, and their sequences used to confirm the identified transcripts as true syntaxins. By enhancing our understanding of the molecular basis underlying tick feeding, as well as the proteins involved in the processes, we hope to identify possible targets for the rational design of a viable tick vaccine.
Thesis (PhD (Biochemistry))--University of Pretoria, 2007.
Biochemistry
unrestricted
APA, Harvard, Vancouver, ISO, and other styles
16

CHMELAŘ, Jindřich. "Transcriptomic and functional analysis of salivary proteins from the tick \kur{Ixodes ricinus}." Doctoral thesis, 2010. http://www.nusl.cz/ntk/nusl-54132.

Full text
Abstract:
This thesis was focused on the identification and characterization of the salivary proteins from Ixodes ricinus, the European vector of Lyme disease and tick-borne encephalitis causative agents. In the first part of this work, the the transcriptomic approach was used in order to identify and describe I. ricinus salivary proteins. The second part is dealing with functional and structural characterization of the salivary protein named IRS-2 (I. ricinus serpin-2).
APA, Harvard, Vancouver, ISO, and other styles
17

Henson, Sonal Prabhulal. "High resolution analysis of genes transcribed in Ixodid tick tissues with special reference to salivary glands of the brown ear tick, Rhipicephalus appendiculatus." Thesis, 2013. http://hdl.handle.net/2263/32958.

Full text
APA, Harvard, Vancouver, ISO, and other styles
18

VANCOVÁ, Marie. "Structural and functional characteristics of spirochetes, causative agents of Lyme disease and salivary glands of the tick Ixodes ricinus." Doctoral thesis, 2006. http://www.nusl.cz/ntk/nusl-45286.

Full text
APA, Harvard, Vancouver, ISO, and other styles
19

SOUČKOVÁ, Nina. "Charakterizace rodiny proteinů o molekulové hmotnosti 18,7 a 19 kDa ze slinných žláz klíštěte \kur{Ixodes ricinus}." Master's thesis, 2009. http://www.nusl.cz/ntk/nusl-50363.

Full text
Abstract:
The recombinant protein c90 was prepared and polyclonal antibodies against this protein were raised. The dsRNA was made for the experiments with RNA interference. The samples from dissected tissues of dsRNA silenced ticks were tested by RT-PCR and Western blot. Results suggest that protein c90 plays a role in the tick body during the reaction to injury. Finally, another experiment with injection of water, G+ and G- bacteria into the ticks was realized. It was found that the members of the 18,7 kDa protein family can create multimers. The overexpression of silenced genes was observed during RNAi experiments despite of expected inhibition of c90 production. These results together with the bioinformatics analysis could mean that these proteins are important the physiology of tick probably as a reaction to injury. However c90 protein is produced only in the first phase of feeding which could mean that it has some role in the tick-host interaction as well.
APA, Harvard, Vancouver, ISO, and other styles
20

BUČINSKÁ, Lenka. "Analýza glykoproteinů ze slinných žláz klíštěte \kur{Ixodes ricinus}." Master's thesis, 2010. http://www.nusl.cz/ntk/nusl-52563.

Full text
Abstract:
I characterized several potential glycoproteins in salivary gland extracts from unfed and partially fed females of ticks Ixodes ricinus using enzyme deglycosylation and lectin labeling. Affinity-based (chromatografic) analysis was applied for isolations of glycoproteins with specificity for GNA (mannose), HPA (N-acetylgalactosamine) and MAA II (sialic acid) lectins. GNA specific 120 kDa glycoprotein was isolated from partially fed females and is modified with N-linked glycans containing {$\alpha$}1,3-mannose. Mass spectrometry analyses confirmed the presence carboxypeptidase M in elution fraction gain with GNA affinity chromatography. GNA specific proteins were purified from unfed female salivary gland extracts. MS analyses identified them as proteins similar to arylsulfatase B and cytoskeletal Sojo protein. Proteins (85 and 56 kDa) isolated with HPA affinity chromatography were characterized as Trappin 12, which is a host protein. MAA II lectin was used for labelling and isolation of 100 kDa protein. N-terminal sequence of the MAA II specific protein predicted similarity with a host protein, Siglec 1. Fucose in salivary gland extract was detected with the labelling of AAA, AAL, UEA I and LTL lectins. Results showed that salivary gland extracts contain {$\alpha$}1,2-; {$\alpha$}1,3- and {$\alpha$}1,6- N-linked fucose and O-linked fucose probably as well. GNA specific proteins were detected in partially fed salivary glands acini type II and III using electron transmission microscopy. Fucose was detected on gut and salivary gland structures using fucose-specific lectin AAL.
APA, Harvard, Vancouver, ISO, and other styles
21

SCHRENKOVÁ, Jana. "Lokalizace izoforem katepsinu L (IrCL) ve tkáních klíštěte \kur{Ixodes ricinus}." Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-166268.

Full text
Abstract:
Two isoforms of the tick Ixodes ricinus digestive peptidases cathepsins L1 and L3 are expressed also in salivary glands. In order to assess their role in this tissue, the specific antibodies against these peptidases were prepared by affinity chromatography and used for their detailed immuno-localization using cutting-edge methods of electron microscopy.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography