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1

Hardré-Liénard, Hélène. "Régulation de l'activation cellulaire par les phosphatases à domaine SH2." Paris, Muséum national d'histoire naturelle, 2001. http://www.theses.fr/2001MNHN0004.

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2

Dorey, Karel. "Mecanismes moleculaires de la regulation de c-abl, une tyrosine kinase a domaine sh2 et sh3." Paris 6, 2001. http://www.theses.fr/2001PA066078.

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La tyrosine kinase de type non-recepteur c-abl est exprimee ubiquitairement chez tous les metazoaires. En plus de son domaine catalytique, c-abl possede des domaines d'interaction proteine-proteine qui sont essentiels pour sa fonction. Si la fonction precise de c-abl est inconnue, elle est impliquee dans une grande variete de processus. L'inactivation du gene a un phenotype pleiotropique conduisant a une mort embryonnaire precoce. L'activation constitutive de c-abl la transforme en un oncogene puissant implique dans des leucemies humaines. Il est donc vital pour la cellule de reguler de maniere extremement precise son activite catalytique. Au cours de ce travail de these, nous avons etudie les mecanismes moleculaires regulant c-abl. La tyr 412 est situee dans la boucle d'activation du domaine catalytique de c-abl. Ce residu est au cur du mecanisme de regulation de l'activite catalytique de c-abl. Son positionnement a l'interieur du domaine catalytique est essentiel au maintien de la forme inactive de c-abl. La phosphorylation de la tyr 412 est requise pour activer l'enzyme. La tyr 412 est un site de trans-autophosphorylation qui permet une boucle d'amplification du signal. Une particularite de la regulation de c-abl est le role d'un domaine de 80 acides amines situe en n-terminal de la molecule et contenant le site de myristoylation. Il interagit de maniere intramoleculaire avec le reste de la molecule. Cette interaction est necessaire pour la regulation de c-abl. Le point commun des formes oncogeniques de c-abl est l'absence de ce domaine. La deletion de ce domaine suffit a rendre c-abl oncogenique. C'est peut-etre la que reside la difference fondamentale entre la forme sauvage et les formes oncogeniques d'abl. L'activite catalytique de c-abl est donc sous le controle d'une combinaison de facteurs -interactions intramoleculaires, interactions proteine-proteine, evenement de phosphorylation- qui permettent d'assurer une reponse appropriee a un stimulus donne.
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3

Courme, Caroline. "Conception de novo et synthèse de ligands non peptidiques potentiels du domaine SH2 de Grb2." Paris 5, 2008. http://www.theses.fr/2008PA05P605.

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Grb2 est une protéine adaptatrice qui intervient dans plusieurs voies de signalisation mitogéniques. Elle est constituée de deux domaines SH3 et d’un domaine SH2, ce dernier reconnaissant les phosphotyrosines situées dans la partie intracellulaire des récepteurs à tyrosine kinase activés. Ces voies contrôlent divers processus comme la prolifération et la survie cellulaire et sont impliquées dans les cancers du sein (Ras/MAPK) et du rein (HGF/cMet). Depuis plus d’une décennie, plusieurs groupes de recherche se sont intéressés à l’inhibition de Grb2, qui ouvrirait de nouvelles perspectives en oncologie. La co-cristallisation de Grb2 avec un de ses ligands endogènes, Bcr-Abl, a permis de définir les pharmacophores essentiels à la reconnaissance par la protéine. De nombreux inhibiteurs peptidiques ou peptidomimétiques ont été développés mais très peu d’inhibiteurs non-peptidiques ont été décrits jusqu’à présent. C’est dans ce contexte que s’est inséré notre programme de recherche, en partant des structures de deux ligands de référence : un peptide développé par l’équipe de C. Garbay et un thiazole non-peptidique développé par Novartis, à trois et deux pharmacophores, respectivement. Nous décrivons dans cette thèse la conception de novo et la synthèse multi-étapes de ligands non﷓peptidiques potentiels de Grb2-SH2. Des composés originaux basés sur les sous-structures dites privilégiées 2-anilinopyrimidine et triazine ont été conçus à partir de la structure cristallographique de Grb2-SH2 avec le peptide de Garbay et coll. De plus, une stratégie de synthèse d’analogues du ligand de Novartis a été développée en exploitant la structure triazine via la chimie ‘click’
Grb2 is an adaptor protein involved in several mitogenic signaling pathways. It consists of two SH3 domains and one SH2 domain, the latter recognizing phosphotyrosines located in the intracellular part of activated tyrosine kinase receptors. These pathways control various processes such as cell proliferation and survival and are involved in the development of breast cancer (Ras/MAPK) and kidney cancer (HGF/cMet). For over a decade, several research groups have been interested in Grb2 inhibition, which could open new perspectives in oncology. The co-crystallization of Grb2 with one of its endogenous ligands, Bcr-Abl, permitted the identification of key pharmacophores for protein recognition. Many peptidic or peptidomimetic inhibitors have been developed but very few non-peptidic inhibitors have been described until today. In this context, we have based our research program on the structure of two reference ligands: a peptide developed by the team of C. Garbay and a non-peptidic thiazole developed by Novartis, with three and two pharmacophores, respectively. We have described in this PhD the de novo design and multi-step synthesis of potential Grb2-SH2 non-peptidic inhibitors. Novel compounds based on 2-anilinopyrimidine and triazine ‘privileged’ scaffolds have been designed using the X-ray structure of Grb2-SH2 co-crystallized with the peptide developed by the team of Garbay. Furthermore, a synthesis strategy has been developed to prepare analogs of Novartis’ ligand, using the triazine scaffold via ‘click’ chemistry
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4

Leroux, Vincent Maigret Bernard. "Modélisation d'inhibiteurs du domaine SH2 de la protéine Grb2 par dynamique moléculaire, docking et criblage virtuel." [S.l.] : [s.n.], 2006. http://www.scd.uhp-nancy.fr/docnum/SCD_T_2006_0220_LEROUX.pdf.

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5

Leroux, Vincent. "Modélisation d’inhibiteurs du domaine SH2 de la protéine Grb2 par dynamique moléculaire, docking et criblage virtuel." Nancy 1, 2006. http://docnum.univ-lorraine.fr/public/SCD_T_2006_0220_LEROUX.pdf.

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Ce manuscrit constitue une étude théorique de l’inhibition de l’activité du domaine SH2 de la protéine Grb2 par la liaison de ligands. La première partie décrit le contexte de ce travail, qui se situe plus généralement à travers le ciblage de Grb2 SH2 parmi les multiples approches de lutte contre le cancer, de l’étude du vivant à l’échelle moléculaire (domaine interdisciplinaire par excellence), et, plus précisément, de la recherche pharmaceutique. La seconde partie s’emploiera à détailler les connaissances disponibles sur la cible au moment de débuter ce travail, en incluant les avancées qui sont apparues en parallèle à ce travail. On trouvera dans la troisième partie un résumé des principaux résultats obtenus au cours de cette thèse. Ceux-ci se classent selon trois approches méthodologiques distinctes : celle de la dynamique moléculaire, du docking et enfin du screening virtuel. On pourra constater que de nouvelles connaissances sur la nature physico-chimique de la liaison de certains ligands sur Grb2 SH2 sont mises en évidence dans le premier cas, tandis que les deux autres approches ont surtout donné naissance à des avancées méthodologiques.
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6

THOME, MARGOT. "Le role du domaine sh2 de la tyrosine kinase p561ck dans la transduction du signal via le recepteur de l'antigene des lymphocytes t." Paris 6, 1995. http://www.theses.fr/1995PA066739.

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Nous avons choisi une approche biochimique pour etudier le mecanisme par lequel la tyrosine kinase p56#l#c#k, et plus specifiquement son domaine sh2, contribue a la transduction du signal via le recepteur t (tcr) et les co-recepteurs cd4 ou cd8, au cours de l'activation des lymphocytes t. Lors de la reconnaissance de l'antigene par les cellules t, le tcr et la molecule cd4 (respectivement cd8) semblent interagir avec la meme molecule du cmh de classe ii (respectivement de classe i) pour former un complexe ternaire stable. La partie cytoplasmique de cd4 ou de cd8 est associee, de facon non covalente, avec la tyrosine kinase p56#l#c#k. En plus d'un domaine kinase, la p56#l#c#k comporte un domaine sh2 qui pourrait etre implique dans des interactions proteine-proteine via un residu tyrosine phosphoryle. Nous avons pu montrer que la p56#l#c#k se lie directement par son domaine sh2 a zap-70 et syk, deux tyrosine kinases homologues associees avec cd3/zeta, apres stimulation des cellules jurkat via le complexe tcr/cd3. De plus, un peptide phosphoryle sur une tyrosine, de sequence a priori optimale pour la liaison au domaine sh2 des tyrosine kinases de la famille src, entre en competition avec zap-70 ou syk pour leur liaison a la p56#l#c#k. Les interactions analogues, via sh2, entre zap-70 ou syk et cd3/zeta, ne sont pas affectees par ce peptide. Le meme peptide est capable d'inhiber l'association du tcr avec cd4 ou cd8 induite par l'activation des cellules jurkat. Par ailleurs, la co-localisation de zap-70 et de cd4 est observee dans des lymphoblastes t humains apres stimulation via cd3. Ces resultats suggerent que l'interaction du domaine sh2 de la p56#l#c#k avec zap-70 ou syk, kinases phosphorylees liees a cd3/zeta, permet l'association de cd4 ou cd8 avec le complexe tcr/cd3/zeta au cours de la stimulation antigenique. Ainsi, ces co-recepteurs seraient recrutes activement par les quelques recepteurs t engages avec les races complexes mhc/ag specifiques, a la surface de la cellule presentatrice ; les processus de reconnaissance et de transduction du signal s'en trouveraient plus efficaces
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7

Lesourne, Renaud. "Bases moléculaires et cellulaires du recrutement des phosphatases à domaine SH2 par les RFcyIIB, des récepteurs pour la portion Fc des IgG inhibiteurs de l'activation cellulaire." Paris 5, 2004. http://www.theses.fr/2004PA05N13S.

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Les RFcyIIB sont des régulateurs négatifs de l'activation cellulaire induite par les récepteurs d'antigène. L'inhibition induite par ces récepteus dépend d'un motif intracytoplasmique, appelé ITIM. Lorsqu'il est phosphorylé, ce motif recrute des phosphatases qui sont les effecteurs de l'inhibition. In vitro, des peptides contenant l'ITIM phosphorylé des RFcyIIB se lient à deux types de phosphatases, les SHP et les SHIP. In vivo, les RFcyIIB phosphorylés recrutent sélectivement les SHIP. Ce travail a consisté à déterminer les bases fondamentales du recrutement sélectif des SHIP par les RFcyIIB. Il démontre, 1) que le degré de phosphorylation des RFcyIIB atteint dans des conditions mimant les situations physiologiques est insuffisant pour leur permettre de recruter les SHP, 2) que le cytosquelette d'actine est nécessaire à l'inbition induite par les RFcyIIB parce qu'il coordonne les interactions entre les SHIP et les RFcyIIB par l'intermédiaire d' une protéine, la filamine
FcyRIIB are negative regulators of cell activation induced by antigen receptors. The inhibition induced by these receptors depend on an intracytoplasmic motif, call ITIM. When phosphorylated, this motif is a docking site for phosphatases wich are the effectors of inhibition. In vitro, peptides containing the phosphorylated ITIM of FcyRIIB bind two types of phosphatases, the SHP and the SHIP. In vivo, phosphorylated FcyRIIB selectively recruit the SHP. This work consisted to determine the molecular and cellular bases of the selective recruitment of SHIP by FcyRIIB. It shows, 1) that the level of FcyRIIB phosphorylation reach under physiological conditions is insufficient for the recruitment of SHP-1 by these receptors, 2) that the F-actin cytoskeleton is necessary for FcyRIIB-depend inhibition because it coordinates the interactions between SHIP and FcyRIIBvia a protein called filamin
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8

Sweeney, Michael Cameron. "Synthetic combinatorial peptide libraries and their application in decoding biological interactions." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1118952919.

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Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains xv, 151 p.; also includes graphics. Includes bibliographical references (p. 134-151). Available online via OhioLINK's ETD Center
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9

Arnaud-Arnould, Mary. "Etude du rôle de la protéine adaptatrice p97/Gab2 dans la signalisation de l'interleukine-2 dans des lymphocytes T humains." Paris 11, 2003. http://www.theses.fr/2003PA112075.

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L'interleukine-2 (IL-2) est produite par les lymphocytes T activés et joue un rôle crucial dans les processus de prolifération, de différentiation en cellules effectrices et d'apoptose secondaire à l'activation. Ses fonctions biologiques reposent sur son interaction avec un récepteur membranaire composé de trois chaînes α, β et γc, dont seules β et γ sont nécessaires à la signalisation intracellulaire. Nous nous sommes intéressés à la signalisation précoce en réponse à l'IL-2 dans des lymphocytes T humains, et en particulier au rôle de la protéine adaptatrice plate-forme Gab2. Nous avons montré que cette protéine est tyrosine phosphorylée en réponse à l'IL-2 et qu'elle s'associe à différents partenaires possédant des domaines SH2 comme la tyrosine phosphatase SHP-2, la lipide kinase PI3K et la protéine adaptatrice CrkL. Nous avons choisi d'étudier plus particulièrement l'interaction Gab2/SHP-2. Nous avons montré que le recrutement et l'activation de SHP-2 via son interaction avec Gab2 sont nécessaires en amont de MEK pour l'activation de la voie Ras/ERK MAPK et permettent à SHP-2 une action en parallèle de la voie RhoA/SRF dans la régulation de l'expression du gène c-fos impliqué dans la prolifération cellulaire. Nous avons également montré que ERK est capable de phosphoryler Gab2 sur sa sérine 623. Cette phosphorylation entraîne une diminution de l'interaction Gab2/SHP-2 qui se traduit par une participation à l'inhibition de la voie ERK et une levée de l'inhibition exercée par l'activité phosphatase de SHP-2 sur STAT5, ce qui module la prolifération des lymphocytes. Ces résultats suggèrent l'implication du complexe Gab2/SHP-2 dans la régulation fine du processus de prolifération cellulaire en réponse à l'IL-2. Ces résultats permettent de mieux comprendre les mécanismes de contrôle de la prolifération des cellules leucémiques humaines et identifient la protéine Gab2 comme un élément régulateur central des voies de signalisation activées par l'IL-2
Interleukin-2 (IL-2) is a major growth factor for T lymphocytes which plays a critical role in cellular proliferation, differentiation and activation-induced cell death. The effects of IL-2 on its target cells are mediated through specific cell-surface receptors, which comprise three subunits α, β and γc. Only β and γc are required to trigger downstream signalling events. We were interested in early signalling events in response to IL-2 in human T lymphocytes and have studied the role of scaffolding adaptor protein Gab2. We report here that Gab2 becomes tyrosine-phosphorylated in response to IL-2 and forms multimolecular complexes with SH2 domain-containing partners such as the tyrosine phosphatase SHP-2, the lipid kinase PI3K and the adaptor protein CrkL. 8ince the role of SHP-2 in IL-2 signalling has not been fully elucidated, we investigated in details the function of Gab2/SHP-2 interaction. We have shown here that IL-2 activates SHP-2 via Gab2. Furthermore, SHP-2 appears to be required upstream of MEK in activation of the Ras/ERK pathway and in parallel to the RhoA/SRF pathway for c-fos promoter regulation and therefore cellular proliferation. Moreover, we have shown that ERK phosphorylates Gab2 on a consensus phosphorylation site, Ser 623. This phosphorylation downregulates the interaction between Gab2 and SRP-2 and consequently the activity of SHP-2, which modulates ERK and STAT5 activation. So, at the initiation of the response, Gab2-activated SHP-2 is required for ERK activation. At later time points, secondary to ERK-mediated phosphorylation of Gab2 S-623, decreased SHP-2 activity helps down-regulating ERK, and allows for STAT5 activation to persist. These results demonstrate that ERK-mediated phosphorylation of Gab2 S623 is involved in fine tuning the proliferative response of T-lymphocytes to IL-2. These results provide new insight on the control of human leukemic cell proliferation and on the critical role of Gab2 in IL-2 signal transduction
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10

Chandler, Brendan. "The SH2 Domain-Containing Adaptor Protein SHD Reversibly Binds the CRKL-SH2 Domain and Knockdown of shdb Impairs Zebrafish Eye Development." ScholarWorks @ UVM, 2018. https://scholarworks.uvm.edu/graddis/878.

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The adaptor protein CT10-Regulator of Kinase (CRK) and the closely related CRK-Like (CRKL) are adaptor proteins that play important roles in many signaling pathways regulating cell proliferation and cell motility. A notable example is their required role in Reelin signaling during development of the laminated structures of the vertebrate central nervous system, including the cerebral cortex, cerebellum, hippocampus, and retina. As adaptors, CRK/CRKL are important in coupling phosphotyrosine signaling to G protein activity to regulate both cell proliferation and changes in the actin cytoskeleton, thereby exerting control over cell motility, and migration. While many proteins that interact with CRK/CRKL have been identified, the diverse roles of these molecules suggest that more remain to be found. Herein is described a novel CRK/CRKL interacting protein, Src Homology 2 domain-containing protein D (SHD), which demonstrates a phosphorylation-dependent interaction with the CRK/CRKL SH2 domain in HEK 293 cells stimulated with hydrogen peroxide, which globally boosts tyrosine phosphorylation by inhibiting tyrosine phosphatases. Treatment with an inhibitor for Src family kinases (SFKs), Src-1, or an inhibitor of Abl/Arg kinases, STI571, reduces peroxide-induced binding of the CRKL-SH2 domain to SHD. We show that overexpression of Abl kinase, but not the SFK Fyn is sufficient to induce binding of the CRKL-SH2 to SHD and that this interaction requires at least one of the five tyrosines in YxxP motifs found in SHD. Using mass spectrometry, we found that Abl phosphorylates SHD on Y144, which is located in a YxxP motif. Mutation of this site to phenylalanine reduces, but does not prevent, Abl-induced binding of SHD to the CRKL-SH2 domain, suggesting that other YxxP sites also facilitate the interaction. A discussion of the cellular consequences of the interaction between SHD and CRK/CRKL is presented. To explore the biological role of SHD, we used the zebrafish to study shdb, a putative ortholog of human SHD. The expression of shdb was unknown and so we performed in situ hybridization and determined that shdb was expressed in the developing nervous system. To study the function of this gene, we used a morpholino to knock down expression of shdb which resulted in significantly reduced eye size. Possible roles of Shdb in eye development are discussed as is future research aimed to elucidate the cellular and developmental mechanisms by which Shdb functions in the developing eye.
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11

Tan, Pauline H. "Sequence Specificity of Src Homology-2 Domains." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1324406526.

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12

Zhang, Yanyan. "Investigation of SH2 Domains: Ligand Binding, Structure and Inhibitor Design." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1259766230.

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13

Feil, Bertram. "Genexpression des Adaptorproteins Shc bei Patienten mit Juveniler Myelomonozytärer Leukämie (JMML) Charkterisierung neuer Spleissformen der SH2-Domäne von Shc /." [S.l.] : [s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=960983627.

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14

Feil, Bertram. "Genexpression des Adaptorproteins Shc bei Patienten mit Juveniler Myelomonozytärer Leukämie (JMML) Charakterisierung neuer Spleißformen der SH2-Domäne von Shc /." [S.l. : s.n.], 2000. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB8937685.

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15

Glasgow, Shane L. Mr. "Determination of the Sequence Specificity of SH2-B1β and SH2-B3 SH2 Domains by a Combinatorial Library Approach." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1282240642.

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16

Huyer, Gregory. "Specificity of SH2 domains and protein tyrosine phosphatases." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0018/NQ44864.pdf.

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17

Giorgetti-Peraldi, Sophie. "Implication des proteines contenant des domaines sh2 et sh3 dans la transmission du signal induit par l'insuline et l'igf-i : role de la phosphatidylinositol-3-kinase et des proteines shc." Nice, 1994. http://www.theses.fr/1994NICE4726.

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Le travail presente dans cette these a porte sur l'implication des proteines contenant des domaines sh2 et sh3, dans le mecanisme d'action de l'insuline et de l'igf-i. Nous avons montre que la phosphatidylinositol-3-kinase (pi-3-kinase) est stimulee par l'insuline dans des cellules insulino-sensibles, les adipocytes de rat. De plus, l'insuline induit une translocation de l'enzyme depuis le cytosol vers la membrane plasmique. Dans des fibroblastes, l'insuline et l'igf-i induisent la phosphorylation sur tyrosine de irs-1 (insulin receptor substrate-1), et son association avec la pi-3-kinase. Cette association est responsable de l'activation de l'enzyme. Dans des fibroblastes transfectes avec l'adnc de shc, les proteines shc sont phosphorylees sur tyrosine en reponse a l'insuline et a l'igf-i et interagissent avec irs-1. La surexpression des ces proteines ne modifie pas l'activation de la pi-3-kinase, mais induit une augmentation de l'activite basale de la mek. De plus, les cellules sont plus sensibles a l'action mitogenique de l'insuline
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18

Okoh, Michael P. "Molecular and biophysical analysis of the non-catalytic PH, TH, SH3 and SH2 domains of Bruton tyrosine kinase (Btk) protein." Helsinki : University of Helsinki, 2002. http://ethesis.helsinki.fi/julkaisut/mat/bioti/vk/okoh/.

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19

Hensmann, Meike. "NMR studies of SH2 domains : structure and phosphopeptide binding." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307082.

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20

Hard, Ryan Lawrence. "Sequence Specificity of BUZ, PDZ, SH2, and Tandem BRCT Domains." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1377005582.

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21

Nicolas, Gaël. "Étude fonctionnelle et structurale de certains domaines des spectrines érythroïdes et non érythroïdes : site de tétramérisation et domaine SH3." Phd thesis, Université Paris-Diderot - Paris VII, 1999. http://tel.archives-ouvertes.fr/tel-00284819.

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Les spectrines, protéines liant l'actine, sont des constituants majeurs du squelette membranaire, réseau multiprotéique localisé sous la membrane plasmique. Érythroïdes ou non érythroïdes (dans ce cas, on les appelle fodrines), les spectrines ont un rôle structural important dans la membrane comme cela a déjà été démontré, pour la spectrine, dans le globule rouge. Elles sont constituées de deux longues chaînes a et ß associées côte à côte en tétramères (aß)2 qui forment les longs filaments du réseau. Chacune des chaînes est composée par la répétition de segments homologues, 22 pour a et 17 pour ß. Ces segments sont constitués de trois hélices a (hélices A, B et C) repliées sur elles-mêmes. Cette succession de structures trihélicoïdales est parfois interrompue par un domaine particulier comme le domaine SH3 (Src Homology 3) présent au milieu de la chaîne a. Les tétramères (aß)2 de spectrine constituent les filaments du squelette membranaire. L'interaction tête-à-tête de deux dimères aß implique les extrémités NH2 de la chaîne a et COOH de la chaîne ß. D'une part la sévérité du défaut d'auto-association et la localisation des mutations associées à celui-ci et d'autre part, les séquences en acides aminés des extrémités impliquées dans le site d'auto-association ont permis de proposer un modèle : la première hélice C isolée de la chaîne a pourrait s'associer aux deux dernières hélices A et B de la chaîne ß pour reconstituer une unité conformationnelle trihélicoïdale semblable à celles observées le long de la molécule. Un défaut dans la formation du tétramère est le support moléculaire le plus fréquemment observé dans les elliptocytoses héréditaires (HE). À l'aide de peptides recombinants, nous avons défini, sur les deux chaînes, les régions nécessaires et suffisantes possédant les caractéristiques pleinement fonctionnelles du site de tétramérisation. Nous avons ensuite, par mutagenèse dirigée, reproduit le lien entre la présence de mutations HE localisées dans les hélices A ou B et le défaut d'auto-association observé dans les globules rouges de patients HE. La présence d'un domaine SH3 localisé au milieu de la chaîne a confère probablement aux spectrine des fonctions autres que le maintien et la stabilité de la membrane. Les SH3, petits domaines protéiques, participent aux interactions protéine/protéine. Le seul partenaire connu du domaine SH3 de la fodrine était la sous-unité a du canal sodium sensible à l'amiloride (ENaC) mais la fonction de ce complexe n'était pas encore caractérisée. À l'aide de différentes méthodes, nous avons remis en cause l'interaction directe entre ENaC et le SH3 de la fodrine. La fonction de ce domaine SH3 étant liée à la nature de son ligand, nous avons donc recherché les partenaires putatifs du domaine SH3 de la fodrine par la technique du double-hybride. 29 partenaires ont été identifiés, regroupés en 19 familles et 10 clones isolés. La spécificité des interactions a été étudiée à la fois par double-hybride, à l'aide de mutants du domaine SH3 de la fodrine produits par mutagenèse dirigée. Les interactions vis-à-vis d'autres domaines SH3 (spectrine ou une protéine de levure non relatée Scd2) ont été également analysées. Enfin, la spécificité de certains partenaires a été confirmée par des études d'interactions in vitro. Deux des protéines les plus spécifiques du domaine SH3 de la fodrine sont des protéines tyrosine-phosphatase PTP. La première est l'isoforme A de PTP de faible poids moléculaire (LMPTPA) mais l'interaction n'a pas été confirmée in vitro. La deuxième, TD14, est une nouvelle PTP dont la seule fonction connue est d'inhiber la formation des foyers tumoraux des cellules surexprimant l'oncogène Ha-ras. Ces PTP pourraient soit déphosphoryler la fodrine, soit être recrutées sous la membrane pour déphosphoryler une autre cible. Nous avons également identifié trois partenaires (N-WASP, Evl et une protéine de la famille des formines) suggérant que les domaines SH3 des spectrines pourraient être impliqués dans les processus de polymérisation de l'actine liés à la mobilité ou la différenciation cellulaire. Mot clés : spectrine, fodrine, tétramérisation, SH3, double-hybride, polymérisation de l'actine
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22

Park, Junguk. "Development of neutral phosphotyrosine memetics as a protein tyrosine phosphatase inhibitor and studies on its inhibition mechanism." Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1133278132.

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23

Nicolas, Gaël. "Etude fonctionnelle et structurale de certains domaines des spectrines erythroides et non erythroides : site de tetramerisation et domaine sh3." Paris 7, 1999. http://www.theses.fr/1999PA077184.

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Les spectrines, proteines liant l'actine, sont des constituants majeurs des squelettes membranaires, reseau multiproteique localise sous la membrane plasmique. Erythroides ou non erythroides (on les appelle alors fodrines), les spectrines ont un role structural important dans la membrane comme cela a deja ete demontre, pour la spectrine, dans le globule rouge. Elles sont constituees de deux longues chaines et associees en tetrameres () 2 formant les longs filaments du reseau. Chacune des chaines est composee par la repetition de segments homologues, constitues de trois helices (helices a, b et c) repliees sur elles-meme. Cette succession de structures trihelicoidales est parfois interrompue par un domaine particulier comme le domaine sh3 (src homology 3) present au milieu de la chaine. L'interaction tete-a-tete de deux dimeres implique les extremites nh 2 de la chaine et cooh de la chaine. Un modele du site de tetramerisation de la spectrine propose que la premiere helice c isolee de la chaine pourrait s'associer aux deux dernieres helices a et b de la chaine pour reconstituer une unite conformationnelle trihelicoidale semblable a celles observees le long de la molecule. Un defaut dans la formation du tetramere est le support moleculaire le plus frequemment observe dans les elliptocytoses hereditaires (he). A l'aide de peptides recombinants, nous avons defini, sur les deux chaines, les regions necessaires et suffisantes possedant les caracteristiques pleinement fonctionnelles de ce site. Nous avons ensuite, par mutagenese dirigee, reproduit le lien entre la presence de mutation he localisees dans les helices a ou b et le defaut d'auto-association observe dans les globules rouges de patients he. Enfin, la presence d'un domaine sh3 confere probablement aux spectrines des fonctions autres que le maintien et la stabilite de la membrane. Apres avoir remis en cause la realite d'une interaction entre le sh3 de la fodrine et la sous-unite du canal sodium sensible a l'amiloride, nous avons recherche des partenaires de ce domaine sh3 en criblant, par double-hybride, une banque de rein de rat. Nous avons identifie plusieurs partenaires suggerant que les domaines sh3 des spectrines pourraient etre impliques dans les processus de polymerisation de l'actine lies a la mobilite ou la differenciation cellulaire.
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24

Kunys, Andrew Richard. "Binding Specificity of SH2 Domains Revealed by a Combinatorial Peptide Library." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1374185732.

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25

Wavreille, Anne-Sophie Marie. "SRC homology 2 domain proteins binding specificity from combinatorial chemistry to cell-permeable inhibitors /." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1164738844.

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26

Singer, Alex Uriel. "Solution structure and electrostatic properties of an SH2 domain/phosphopeptide complex." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ35322.pdf.

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27

Yuth, Kenneth. "Characterizing the Phosphorylation State of Tie2 using SH2 Domain Fusion Proteins." VCU Scholars Compass, 2011. http://scholarscompass.vcu.edu/etd/275.

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The cardiovascular system develops through two distinct processes in embryogenesis: vasculogenesis, whereby the primary plexus in the heart is formed along with embryonic and extraembryonic vasculature, and angiogenesis, which begins after vasculogenesis and results in the refinement and maturation of the branched vessel system. In pathological angiogenesis, tumors expand by releasing pro-angiogenic factors in response to hypoxic conditions. The Tie receptors, Tie1 and Tie2, are receptor tyrosine kinases that are integral to angiogenic pathways. A family of Angiopoietins, Ang1-4, have been shown to act as ligands for Tie2, of which Ang1 and Ang2 are best characterized. Activation of the receptor causes dimerization and autophosphorylation, whereby adaptor proteins recognizing the phosphorylated tyrosine activate downstream signaling via their Src homology 2 (SH2) domains. Currently there are no phosphospecific antibodies for Tie2, therefore, identifying critical residues responsible for certain pathways remains difficult. In our study, we aim to use purified SH2 domains of known binding partners to Tie2 to assess the phosphorylation state of the receptor under various cellular conditions and settings, utilizing immunoprecipitation and western blotting. Unexpectedly, we found that Tie2 can bind non-specifically to nickel sepharose when the SH2 proteins were used as antibody mimetics, and was unable to be consistently precipitated in Protein A sepharose when used in conjunction with a monoclonal YFP antibody. Under the latter conditions however we were able to precipitate the SH2 protein itself. When immunoprecipitations were used with cobalt activated IMAC beads, we were able to precipitate Tie2 in overexpressed systems using the SH2 domains of Shp2 N-C and Grb2. As expected, phosphorylation of Tie2 in the presence of its orphan receptor Tie1 was attenuated compared to wild-type levels. Based upon available data, we anticipate this method as a useful tool to assess the phosphorylation state of Tie2 and its signaling pathways in the near future.
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28

Byrne, Eilis Mary. "Structural and functional analysis of SHP1, an SH2 domain containing protein tyrosine." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365723.

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29

Ferrari, Giovanna Maria. "The interaction of the α2 chimaerin SH2 domain with target proteins." Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325678.

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30

Reinholt, Brad Michael. "Inactivation of Stac3 causes skeletal muscle defects and perinatal death in mice." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/76784.

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The Src homology 3 domain (SH3) and cysteine rich domain (C1) 3 (Stac3) gene is a novel gene copiously expressed in skeletal muscle. The objective of this research was to determine the role of Stac3 in development, specifically in skeletal muscle. We achieved this objective by evaluating the phenotypic effects of Stac3 gene inactivation on development in mice. At birth homozygous Stac3 null (Stac3-/-) mice died perinatally and remained in fetal position with limp limbs, but possessed otherwise normal organs based on gross and histological evaluations. The primary phenotypes displayed at term in Stac3-/- mice were reduced late gestational body weights, increased prevalence of myotubes with centrally located nuclei and severe deformities throughout all skeletal muscles. At embryonic day 18.5 (E18.5) Stac3-/- mice displayed a 12.7% reduction (P < 0.001) in weight compared to wild type (Stac3+/+) or heterozygous (Stac3+/-) littermates while at E15.5 body weights and morphology were similar. At birth (P0) and at E17.5, Stac3-/- mice had 59% and 24% (P < 0.001) more myotubes with centrally located nuclei, respectively, than Stac3+/- or Stac3+/+ littermates. Stac3-/- mice also displayed increased myotube and myofiber cross sectional area at P0 (P < 0.001) and E17.5 (P < 0.05) with disorganized fiber bundling. Overall, these data show Stac3 is necessary for development of viable offspring and suggest Stac3 plays a critical role in fetal development where its primary phenotype is exhibited in skeletal muscle.
Master of Science
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31

Phee, Hyewon. "Studies of SH2 domain-containing Inositol 5-Phosphatase in FcγRII-mediated negative signaling /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486572165278681.

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32

Ghosh, R. "Interactions of SH3 domains in adaptor proteins." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1331882/.

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This thesis explores the interactions between adaptor proteins containing Src homology domain 3 (SH3) domains and their potential binding partners. Biochemical, biophysical and in vivo studies were used to investigate the structure, function and dynamics of two SH3-containing adaptors CIN85 and Grb2 in apo and ligand bound states. The project aimed to understand the role of CIN85 and Grb2 as key modulators in signalling cascades and the significance of their interactions with other proteins at the physiological level. The interaction between CIN85 and Cbl/Cbl peptides was investigated. The global architecture and dynamics of CIN85 in apo and Cbl bound states were reported for the first time. NMR studies reported that all three SH3 domains of CIN85 binds to Cbl derived peptides in CIN85ABC, however the interaction have a complex mechanism due to existence of complex dynamics between the SH3 domains and linker regions. However, the study identifies that the SH3 domains in CIN85 works in cooperation with each other with the linkers contributing towards the dynamics and global conformation of CIN85 in the presence and absence of Cbl, which is yet to be understood. The interaction between CIN85 and ubiquitin was investigated by in vitro and in vivo approaches. Ubiquitin binds to all three isolated SH3 domains of CIN85 with diverse affinities in vitro. However the complex between CIN85ABC and ubiquitin was weak and physiologically insignificant. No interactions were observed in cell studies between CIN85ABC and CIN85FL with ubiquitin. Finally, the complex between Grb2 SH3C domain with FGF receptor 2 peptide shows a novel mode of interaction investigated using NMR and docking studies. This work shows that SH3-adaptors have discrete preference for ligands and cannot be generalised as linkers in signalling cascades. Each SH3 domain in adaptors displays their function and subtle regulatory character that is interwoven with their structure and dynamics.
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Grantcharova, Viara. "Folding mechanism of the src SH3 domain /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/9231.

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34

Ming-Lum, Andrew N. "The role of SH2-domain inositol 5' phosphatase in the inhibition of macrophage activation." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/41998.

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Interleukin-10 (IL-10) is an anti-inflammatory cytokine essential for maintaining immune homeostasis. One of its major targets is the macrophage where it inhibits production of pro-inflammatory cytokines, chemokines and other soluble mediators. However, the intracellular signaling mechanisms by which IL-10 achieves macrophage deactivation remain under intense investigation. Our studies suggest that in addition to canonical STAT3 signaling, IL-10 mediates its early phase anti-inflammatory response through SHIP1 in a STAT3-independent manner. Upon macrophage activation by bacterial lipopolysaccharide, the phosphoinositide 3′ kinase (PI-3 kinase) pathway is activated to produce cytokines such as tumor necrosis factor α (TNFα). SHIP1 is a negative regulator of the PI-3 kinase pathway and its activation downstream of the IL-10 receptor suppresses PI-3 kinase-initiated signals that trigger transcriptional elongation of TNFα and other pro-inflammatory related genes. We next investigated whether SHIP1 activation could mimic the anti-inflammatory actions of IL-10. We screened for small-molecule activators of SHIP1 and isolated the meroterpenoid compound Pelorol. Pelorol and its derivatives specifically enhanced SHIP1’s phosphatase activity and thus suppressed inflammation in macrophage cultures, and in murine models of endotoxic shock, acute anaphylaxis, and inflammatory bowel disease. Closer examination of SHIP1’s enzyme kinetics indicated that SHIP1 is subject to allosteric activation by its product phosphatidylinositol-3,4-bisphosphate (PI-3,4-P₂). We subsequently identified a previously unrecognized C2 domain residing C-terminal of SHIP1’s phosphatase domain which is required for its allosteric activation and is the binding site for both PI-3,4-P₂ and the small-molecule SHIP1 agonists. Bioinformatic and structural analyses also revealed another previously unappreciated domain located N-terminal of SHIP1’s catalytic domain. Using NMR spectroscopy, we characterized this domain as having pleckstrin homology (PH) domain-like topology. We demonstrate that SHIP1’s PH-related (PH-R) domain participates in recruiting SHIP1 to the plasma membrane upon cell stimulation via direct interactions with phosphatidylinositol-3,4,5-trisphosphate. The PH-R domain is essential for SHIP1 inhibition of FcR-dependent phagocytosis and represents another target to which to develop modulators of SHIP1 function. Together, this work suggests that IL-10 activation of SHIP1 is important in its inhibition of macrophage activation, and that mimicking IL-10 with small-molecule SHIP1 agonists could be an effective and viable approach to treating various inflammatory and autoimmune conditions.
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Pauls, Samantha. "Molecular mechanisms controlling SH2 domain-containing inositol 5’phosphatase (SHIP) function in B cells." The American Association of Immunologists, Inc, 2016. http://hdl.handle.net/1993/31875.

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B lymphocytes are an important type of immune cell that contributes to pathogen clearance. When dysregulated, these cells contribute significantly to diseases such as autoimmunity, allergy and B cell cancers. Here we examine an important regulatory circuit that involves the lipid phosphatase SHIP, a key regulator of the PI3K signaling pathway. SHIP was first described as the major effector of inhibitory IgG receptor FcγRIIB, which downregulates B cell antigen receptor (BCR) signaling pathways when co-engaged. However, it is also known to inhibit signaling downstream of several other receptors, both activating and inhibitory. Here we examine the regulation and function of SHIP in B cells, focusing on the inter-related influences of binding partners, tyrosine phosphorylation and subcellular localization dynamics. First, we assess interaction of SHIP to selected candidate binding partners using an in vitro screening approach. The two most robust interactions were further characterized with respect to dissociation constant. These were: a novel interaction between SHIP phospho-Tyr944 and the SH2 domain of Nck, and a known interaction between the SH2 domain of SHIP and FcγRIIB phospho-Y292. Next, we perform the first examination of SHIP Tyr944. We provide evidence that it contributes to interaction with Nck after BCR engagement and is required for inhibition of actin turnover by SHIP. Finally, we perform the first detailed examination of the mechanisms controlling SHIP localization in human B cells stimulated through the BCR with and without co-engagement of FcγRIIB. We discover that SHIP is recruited to the plasma membrane equally in both stimulation contexts, however FcγRIIB co-ligation results in reduced mobility of SHIP molecules at the cell periphery. We identify a novel and essential role for Syk kinase in promoting SHIP membrane localization, tyrosine phosphorylation, and interaction with known binding partner Shc1. Together, these results provide significant and exploitable insight into the molecular control of a clinically important regulator of B cell responses.
February 2017
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36

Oldenhof, John. "SH3 binding domains in the dopamine D4 receptor." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0017/NQ45764.pdf.

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37

Sandoz, Jacqueline S. "Differentiation specific functions of the Bin1 SH3 domain." Thesis, University of Ottawa (Canada), 2002. http://hdl.handle.net/10393/6100.

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A significant percentage of breast and prostate tumours have a missing or aberrantly expressed Bin1 protein. However, preliminary work in skeletal muscle has shown that Bin1 may also be involved in regulating differentiation. Based on the variable roles attributed to Bin1, we proposed a hypothesis in which distinct domains of Bin1 regulate different functions of the protein. This study examines one particular domain of Bin1, the SH3 domain, through a dominant negative approach in a mouse model. Overexpression of the SH3 domain using a broadly expressed promoter resulted in a skeletal muscle phenotype that included large myofibre diameter in vivo and an inability to complete the differentiation process in vitro. Importantly, these deficits were not accompanied by disruptions in apoptosis, increased cell proliferation or tumorigenesis. These results suggest that Bin1 has distinct functions that are mediated by the modular SH3 domain and separate from its role in cell cycle regulation.
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Campbell, Stephen James. "Molecular modelling of SH2 domain interactions and 'in silico' mutagenesis at the protein-protein interface." Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410627.

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39

Cann, Nansi Emma. "Characterisation of #alpha#-chimaerin isoforms and #alpha#2 SH2 domain mutants expressed in neuroblastoma cells." Thesis, University of London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325534.

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40

Taylor, Jonathan D. "Exploitation of NMR in the analysis and screening of fragment ligands for an SH2 domain." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1446548/.

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A fragment-based approach to drug design has recently emerged in which small chemical groups that bind to adjacent sites on a receptor are identified, optimised, and linked together to generate a high-affinity lead compound. Due to its sensitivity, nuclear magnetic resonance (NMR) is a particularly useful technique for the detection of low-affinity fragment binding. An aim of this project was to explore further the utility of NMR with regards to fragment ligand binding using a well- understood model system - the Src Homology 2 (SH2) domain from v-Src kinase. This choice was supported by a large body of structural, functional, and thermodynamic data, coupled with a decade of pharmaceutical investigation into several SH2 domains. Our ongoing biophysical studies of v-Src SH2 required determination of the apo solution structure of this domain. A high quality structural ensemble was obtained using standard NMR techniques and a combination of manual and automated assignment methods. The internal hydrogen bonding, ionisation states, and backbone dynamics of the apo v-Src SH2 domain was also explored using NMR. The perturbation of v-Src SH2 backbone chemical shifts and dynamics by interaction with fragment ligands yielded insights into SH2 domain binding behaviour and specificity. Computational approaches were used to identify potential fragment ligands for v-Src SH2. A small library of these molecules were screened in vitro using a recently-proposed 19F-NMR competition screening approach, which was optimised for the detection of low-affinity fragments. Follow-up NMR and calorimetry experiments confirmed the screening results and provided further characterisation of the novel fragment ligands. Such compounds may be useful as phosphotyrosine mimetics in SH2-related drug design. A novel 31P-based screening experiment was also proposed. These studies have furthered our understanding of the SH2 domain, in terms of its binding specificity and drug design, and of the NMR screening approaches useful for fragment-based lead discovery.
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Ray, Avi Andrew. "SH3 binding domains in the dopamine D¦3 receptor." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0018/MQ45843.pdf.

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42

Heseltine, Sophie Jane. "Developing a toolbox of Affimer reagents targeting SH2 domains to study protein-protein interactions in disease." Thesis, University of Leeds, 2019. http://etheses.whiterose.ac.uk/22642/.

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Src Homology 2 (SH2) domains are phosphotyrosine-binding modules that mediate a range of protein-protein interactions. These domains are found in over 120 human proteins and are involved in several signalling pathways that can become deregulated in diseases such as cancer. Research into the role of individual SH2s in disease has been hampered by a lack of protein-specific reagents available for intracellular functional assays. Specificity of reagents is difficult to achieve, due to the high sequence and structural homology of the domains. Research presented in this thesis investigates the use of a novel non-immunoglobulin binding protein, the Affimer, as an SH2 domain research reagent. The project aimed to isolate Affimer reagents that bound to SH2 domains in a protein-specific manner, and to explore their ability to inhibit their target in several in vitro assays. Affimer binders were raised against 38 SH2 domains and tested in protein microarrays to determine specificity; revealing the isolation of 62 protein-specific reagents. A subset of Grb2 SH2-binding Affimer reagents were used in in vitro characterisation studies, demonstrating high binding affinities for their target and competitive inhibition of the domain. Selected binders used in mammalian cell-based assays also showed disruption of Grb2-mediated signalling, evidenced by reduced phosphorylation of a downstream target. The SH2-binding Affimer reagents tested in this study showed comparable qualities to other previously SH2-targeting binding proteins, with many displaying higher specificity for their target. The Affimer therefore has good potential for use in the study of SH2 domain-mediated signalling. In particular, utilising SH2-binding Affimer proteins as a screening tool in functional cell-based assays is an exciting future prospect.
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Quraishi, Omar. "Expression, purification, and NRM characterization of the N-terminal SH2 domain of protein tyrosine phosphatase 1C." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=55525.

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The N-terminal SH2 domain of protein tyrosine phosphatase 1C (SHN1C) was expressed in E. coli as a fusion to maltose-binding protein (MBP) using two different polylinkers, one comprising of the traditional recognition motif for FXa (IEGR) and the other for thrombin (FNPR), as part of an effort to resolve its three-dimensional solution structure by NMR spectroscopy. The construct encoding the thrombin cleavage site provided a fusion protein that exhibited superior proteolytic cleavage efficiency. This allowed the production of sufficient SHN1C to allow us to examine its behavior in aqueous solutions. Purification of SHN1C from MBP and other cleavage products could only be accomplished by allowing the protein of interest to precipitate at pH 7.0. Likewise, SHN1C is highly insoluble in aqueous solvents, particularly between pH 5.5-7.0, thus making it impossible to perform proton resonance assignments. Binding studies between the SHN1C-containing fusion protein and two phosphotyrosyl-containing peptides (derived from the C-terminal end of PTP 1C), pNPP, and pTyr were performed using NMR methods. No evidence for binding was found for each case. It is therefore postulated that SHN1C may regulate the catalytic activity of PTP 1C by interacting with specific regions of the full length enzyme via a phosphotyrosine-independent mechanism.
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Broadbridge, Robert James. "Design and synthesis of novel inhibitors to the SH2 domain of the protein tyrosine kinase p56lck." Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494712.

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45

Shedden, Elizabeth. "Interactions of ADAM15 splice variants with SH3 domain proteins." Thesis, University of East Anglia, 2015. https://ueaeprints.uea.ac.uk/53418/.

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A Disintegrin And Metalloproteinase 15 (ADAM15) is a membrane-bound metalloproteinase which has been shown to be significantly raised throughout breast cancer progression. The intracellular domain (ICD) of ADAM15 exists in multiple splice variants that contain varied combinations of polyproline regions, which interact preferentially with proteins containing Src Homology 3 (SH3) domains. Patients suffering from node-negative breast cancer exhibited a poorer prognosis when expressing high levels of variant A and B whereas those patients suffering from node-positive cancer exhibited an improved prognosis when expressing high levels of ADAM15 variant C. Nuclear Magnetic Resonance (NMR) spectroscopy titrations were used to elucidate the interaction interface between the ADAM15 ICD variants and the SH3 domains of Grb2, Src and Brk. Chemical Shift Perturbations (CSPs) indicated that Grb2 interacted with all ADAM15 ICD variants via residues 22Glu, 44Trp and 56Phe. Analysis of the common regions of the ICD variants implicated the polyproline region 4 in this interaction. The Src SH3 domain interacted with ADAM15 B, C and E via residues 17Arg, 21Asp, 40Trp and 56Ser-58Tyr; residues which are present in the hydrophobic pocket of the domain. This interaction likely involves a RPLPXDPV motif apparent in polyproline regions 2 and 3 of the ADAM15 ICD. The Brk SH3 domain also interacted with ADAM15 B via residues 34Arg, 56Trp, 74Val, 77Asn and 79Leu in a manner similar to the internal interaction of the Brk SH3 domain with its own linker region. ADAM15 D does not interact with any of the SH3 domains as it does not include any polyproline regions. This work has highlighted the manner by which certain SH3 domains preferentially interact with the polyproline regions of the ADAM15 ICD and open a line of investigation into the downstream functions of these interactions particularly with regards to breast cancer expression.
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Ulmer, Tobias Sebastian. "Nuclear magnetic resonance spectroscopic studies of the intracellular tails of integrin #alpha#IIb#beta#3, the Fyn kinase SH3-SH2 domain pair and the perdeuterated second type 2 module of fibronectin." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393367.

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47

DOUANGAMATH, ALICE. "Etudes structurales des domaines sh3 presentant des modes d'interaction inconventionnels." Paris 11, 2001. http://www.theses.fr/2001PA112143.

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Les domaines sh3 (src homology 3), composes d'environ 60 acides amines, sont des modules d'interactions proteines-proteines impliques dans de nombreux processus biologiques. Un effort intensif a permis de caracteriser les complexes de certains domaines sh3 avec leurs ligands dont la sequence primaire contient le motif canonique pxxp. Des resultats recents ont demontre que le mode d'interaction des domaines sh3 est beaucoup plus varie qu'il ne l'etait suppose jusqu'ici. Au debut de la presente etude, il n'existait que peu de donnees crystallographiques au sujet de ces nouveaux types d'interaction. Afin de combler cette lacune nous avons choisi d'etudier les domaines sh3 de deux proteines, pex13p et abp1p. La structure de pex13psh3 a ete determinee par la technique de diffraction anomale a plusieurs longueurs d'ondes (multiple anomalous diffraction : mad) a une resolution de 2. 9 a. Elle revele la presence de deux sites d'interaction differents pour les deux ligands de pex13p : pex14p et pex5p. Pex14p contient dans sa sequence primaire le motif pxxp et a ete modelise dans le site d'interaction du motif pxxp. Le site d'interaction de pex5p est localise dans une cavite hydrophobe entre les boucles rt et n-src. Le domaine sh3 de pex13p interagit avec le motif wxxxf od pex5p qui adopte une conformation en helice alpha. Une barriere creee par des extensions des deux boucles rt et n-src separe les deux sites d'interaction. La structure de abp1p(sh3) a ete resolue par remplacement moleculaire a haute resolution (1. 3 a) ce qui a permis une determination precise d'un modele moleculaire qui pourra servir de base dans des etudes ulterieures des domaines sh3. De plus, la representation de la charge electrostatique nette a la surface de ce domaine indique la presence d'une region de charge negative formee par trois residus acides. Cette zone est localisee en dehors du site d'interaction pour le motif pxxp et aux antipodes de la region de specificite. Il est interessant de remarquer que ces trois residus sont hautement conserves dans la sequence primaire d'autres domaines sh3 mais ne le sont pas dans le cas present. Cette etude par diffraction des rayons x a revele des particularites dans les types d'interaction des domaines sh3 presentes. Ceci suggere une grande adaptabilite des domaines sh3 pour reconnaitre specifiquement leurs ligands.
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48

Huynh, Nhat Huu. "Characterization of the RRM2 domain of splicing factor ASF/SF2." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p1457389.

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Thesis (M.S.)--University of California, San Diego, 2008.
Title from first page of PDF file (viewed November 13, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 64-69).
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49

Shi, Xiaoli. "Etude de la spécificité des interactions protéine-protéine : application au complexe Alix-domaine SH3 des Src Kinases." Thesis, Aix-Marseille 1, 2011. http://www.theses.fr/2011AIX10024/document.

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Les domaines SH3 (Src Homology domain) représentent l'un des modules protéiques le plus largement répandu dans la nature. Ils participent à des interactions intra- et intermoléculaires avec d’autre partenaires au travers de la formation et de la dissociation de complexes multi-protéiques. Le gène nef du Virus d'Immunodéficience Humain (VIH-1) code pour la protéine nef, importante pour la réplication du virus et le développement optimal du SIDA (Syndrome d’Immunodéficience Acquise) chez les personnes infectées. De précédentes études ont mis en évidence que la protéine nef utilise un mode « tertiaire » d’interaction pour mettre en place une affinité et une sélectivité élevées envers les domaines SH3 des kinases de la famille Src (SFKs). Savoir si cette stratégie de reconnaissance tertiaire des domaines SH3 peut être retrouvée dans des protéines cellulaires humaines est donc une question importante pour évaluer le degré de spécificité de la protéine nef comme cible anti-HIV. Nous avons identifié Alix (ALG-2 [apoptosis-linked gene 2]-interacting protein X) comme protéine originale interagissant avec le domaine SH3 de la kinase de cellules Hématopoïétique (Hck). Alix possède une sélectivité comparable à nef envers les domaines SH3 de SFKs. Nous avons combiné une analyse biophysique et structurale, alliant des méthodes telles que la microcalorimetrie à titration isotherme(‘ITC’), la Résonance Plasmonique de Surface (‘SPR’), des méthodes in vitro dites de ‘GST pulldown’, l'interférométrie (‘NPOI’), la Résonance Magnétique Nucléaire (‘NMR’ - HSQC) et la diffusion des rayons X aux petits angles (SAXS) pour explorer les caractéristiques définissant le mode d’interaction entre Alix et le domaine SH3 de la kinase Hck. Cette étude démontre que la protéine cellulaire Alix est unique, structurellement différente mais fonctionnellement semblable à nef
Src homology (SH) 3 domains is one of the most wide-spreaded protein modules found in nature. They mediate both inter- and intra-molecular protein-protein interactions (PPIs) through the formation and dissociation of multi-protein complexes. These SH3-mediated interactions are responsible for signal transduction, cytoskeleton organization and other cellular processes. The nef gene of Human immunodeficiency virus (HIV-1) encodes the HIV-1 Nef protein, which is important for optimal virus replication and development of AIDS (acquired immunize deficiency syndrome) in HIV-1 infected persons. Previous studies show that the HIV-1 Nef protein uses a “tertiary” binding mode to achieve high affinity and selectivity toward SH3 domains of Src-family kinases (SFKs). Whether this strategy of ‘tertiary’ binding mode of SH3 domains can be found in human cellular proteins, besides HIV-1 Nef, is an important question in the specificity of the HIV-1 Nef protein as an anti-HIV target. We identified Alix (ALG-2 [apoptosis-linked gene 2]-interacting protein X) as a novel protein interacting with Hemopoietic cell kinase (Hck) SH3 domain. Alix has similar selectivity towards SH3 domains of SFKs as the HIV-1 Nef. We have combined biophysical and structural biology analysis, including ITC (isothermal titration calorimetry), SPR (surface Plasmon resonance), GST (glutathione S-transferase) pull-down, interferometry, HSQC (heteronuclear single quantum coherence) and SAXS (small-angle X-ray scattering) to explore the characteristics of Alix-SH3 recognition mode. This study shows that Alix as a unique cellular protein, which is structurally different but functionally similar in recognizing HIV-1 Nef. The structural information of the Alix-Hck association facilitates the understanding of how Hck and Alix assist viral budding and cell surface receptor regulation
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50

Pamonsinlapatham, Perayot. "Etudes de l'interaction RasGAP/CAPNS1 et développement d'inhibiteurs du domaine SH3 de RasGAP." Paris 5, 2008. http://www.theses.fr/2008PA05P627.

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Indépendamment de son activité GEF (guanine exchange factor) désactivant Ras sous forme GDP, RasGAP agit comme un effecteur de Ras majeur dans les cellules tumorales impliquant de nouvelles voies de signalisation. Une approche innovante, pour valider l’inhibition d’interactions moléculaires de la protéine cible RasGAP a été la sélection d’aptamères peptidiques, que nous avons développés contre son domaine SH3 comme cible. Nous avons utilisé une approche combinatoire d’aptamère peptidique pour sélectionner une collection de ligands peptidiques spécifiques du domaine SH3 de RasGAP. Nous avons cartographié les sites de liaison de l’aptamère peptidique en présence d’un ensemble de mutation SH3-RasGAP en système de levure double hybride (AptaPrint). Nous avons étudié l’effet biologique d’un aptamère RG 27 qui cible une poche délimitée par les résidus D295/7, L313 et W317. Cet aptamère a un effet anti-prolifératif et anti-apoptotique qui n’est pas dépendant des caspases sur les cellules tumorales. Il inhibe l’interaction RasGAP et Aurora B. Dans la deuxième partie, nous avons décrit une nouvelle cible du domaine SH3 de RasGAP et étudié son interaction avec la petite sous unité commune des calpaïnes ubiquitaires Capns1. Cette petite sous-unité est un partenaire du domaine SH3 de RasGAP. L’interaction entre RasGAP et Capns1 est mise en évidence par coimmunoprécipitation et RasGAP pull-down et par microscopie confocale. Nous avons précisément étudié la migration de cellules PC3 (Raswt) et PC3-RasV12, qui expriment de façon stable la mutation de Ras oncogénique et la plus fréquemment retrouvée dans les cancers humains. Le complexe SH3-RasGAP/Capns1 est retrouvé augmenté d’un facteur 2 dans les protrusions des cellules C3-RasV12 par rapport celles des cellules PC3. En perturbant ce complexe par RNA interférence RasGAP, la migration cellulaire et l’apoptose des cellules exprimant la mutation RasV12 sont toutes deux perturbées, ce qui indique que RasGAP agit comme effecteur de Ras
Regardless of its activity as guanine exchange factor (GEF), Ras disabling form GDP, RasGAP acts as a major effector of Ras in tumor cells involving new signaling pathways. The innovative approach to validate the inhibition of molecular interactions of the protein RasGAP is the selection of peptidic aptamers, which we have developed against its SH3 domain. We used a combinatorial approach of the peptide aptamer to select a collection of specific peptides against the RasGAP-SH3 domain. We have mapped the binding sites of aptamer in the presence of a SH3-RasGAP mutation system in yeast double hybrid (AptaPrint). We studied the biological effect of the RG 27 aptamer, which target a pocket bounded by residues D295/7, L313 and W317. This aptamer has anti-proliferative and anti-apoptotic effect which is not dependent on caspases in tumor cells. RG27 inhibits the RasGAP and Aurora B interactions. In the second part, we described SH3 domain of RasGAP as a new target and studied its interaction with the small common subunit ubiquitous calpains (Capns1). This small sub-unit is a partner in the SH3 domain of RasGAP. The interaction between RasGAP and Capns1 is highlighted by co-immunoprecipitation and RasGAP pull-down and confocal microscopy. We have precisely studied the migration of PC3 cells (Raswt) and PC3-RasV12, which expresses a stable oncogenic Ras that is mostly found in human cancers. The SH3-RasGAP/Capns1 complex is found increased by a factor of 2 in cells PC3-RasV12 protrusions in contrast to parental PC3. In this complex, siRNA RasGAP disrupts cell migration and apoptosis RasV12 harboring cells, indicating that RasGAP acts as effector of Ras
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