Tyrosine Kinases and Lymphocyte Activation

酪氨酸激酶和淋巴细胞激活

• 批准号: 8372345
• 负责人: ROBERT L GEAHLEN
• 金额: $ 33.52万
• 依托单位: PURDUE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-01 至 2017-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8372345
• 关键词: Accounting; Animals; Antibodies; Antigen Receptors; Apoptosis; Apoptotic; B-Cell Development; B-Lymphocytes; Binding; Binding Proteins; Biochemical; Cell Survival; Cell physiology; Cells; Chemicals; Clonal Expansion; Code; Complex; Coupled; Couples; Cultured Cells; Cytoplasmic Protein; Docking; Drug Delivery Systems; Engineering; Enzymes; Evaluation; Genes; Goals; Growth; Immune; Immune system; Infection; Ligation; Location; Lymphocyte Activation; Mature B-Lymphocyte; Mediating; Methodology; Molecular; Mus; N-terminal; Nature; Outcome; Pathway interactions; Peptides; Phosphorylation; Phosphotransferases; Phosphotyrosine; Physiological; Play; Proliferating; Property; Protein Family; Protein Kinase; Protein Tyrosine Kinase; Proteins; Proteomics; Receptor Aggregation; Receptors, Antigen, B-Cell; Regulation; Reporting; Research; Role; Signal Pathway; Signal Transduction; Site; Stimulus; Stress; Testing; Therapeutic Agents; Tyrosine; Tyrosine Phosphorylation; Work; analog; anti-cancer therapeutic; base; chemical genetics; extracellular; inhibitor/antagonist; leukemia/lymphoma; mouse model; novel; pathogen; protein function; protein protein interaction; receptor; receptor coupling; response; src Homology Region 2 Domain; ward

DESCRIPTION (provided by applicant): The long-term goal of our research has been to understand how cytoplasmic protein-tyrosine kinases regulate the growth properties of immune cells in response to extracellular stimuli. Our current focus is on the tyrosine kinase, Syk, which was discovered as part of this work. Through its substrates and binding partners, Syk couples the B cell receptor for antigen (BCR) to multiple intracellular signaling pathways resulting in one of several possible physiological outcomes that can vary from proliferation to apoptosis depending on the repertoire of downstream signals that are sent. Syk has functions not easily explained by its known activities and its known substrates at the site of the clustered BCR complex including an ability to suppress cellular responses to apoptotic stimuli. This function has made Syk an attractive target for anti-cancer therapeutics. The mechanism by which Syk dissociates from the BCR complex and is subsequently targeted to other cellular docking sites will be investigated as will the nature of these alternative binding proteins. The putative substrates that Syk phosphorylates as a consequence of its re-localization, as identified by sophisticated mass spectrometric analyses, will be characterized and the consequences of their phosphorylation analyzed to investigate new pathways that are regulated directly by Syk. These studies will be extended to primary B cells using cells derived from a new mouse model in which the activity of Syk can be unambiguously inhibited using a powerful chemical genetics approach. We plan to accomplish three specific aims: 1) to characterize the role of tyrosine-130 phosphorylation in the modulation of Syk-receptor and Syk-protein interactions, 2) to characterize novel Syk substrates and signaling pathways identified through proteomic and phosphoproteomic screens, and 3) to characterize the role of Syk in signaling in primary B cells through chemical genetics. Methodologies to be employed include 1) biochemical and physical evaluations of protein-peptide and protein- protein interactions, 2) proteomic and phosphoproteomic analyses of interacting proteins and kinase substrates, 3) molecular and cellular studies on protein function and 4) the use of chemical inhibitors to block kinase function in cells derived from genetically manipulated mice expressing an engineered kinase. PUBLIC HEALTH RELEVANCE: This project focuses on an enzyme known as Syk that is absolutely required for the B lymphocyte components of the immune system to recognize and respond to infectious pathogens. Its activation can stimulate the responding B lymphocytes to expand in numbers and develop the ability to make antibodies to ward off the infection. Since, this ability of Syk to trigger a proliferative response can also provide a way for leukemia and lymphoma cells to proliferate, an understanding of Syk's functions is critical for identifying suitable therapeutic agents and drug targets.

描述（由申请人提供）：我们研究的长期目标是了解细胞质蛋白酪氨酸激酶如何调节免疫细胞对细胞外刺激的生长特性。我们目前的重点是酪氨酸激酶Syk， 是在这项工作中发现的通过其底物和结合伴侣，Syk将抗原的B细胞受体（BCR）偶联到多个细胞内信号传导途径，导致一个 几种可能的生理结果，可以从增殖到凋亡，这取决于所发送的下游信号的库。Syk具有不易通过其已知活性及其在成簇BCR复合物位点处的已知底物来解释的功能，包括抑制细胞对凋亡刺激的应答的能力。这种功能使Syk成为抗癌治疗的有吸引力的靶标。将研究Syk从BCR复合物中解离并随后靶向其他细胞对接位点的机制，以及这些替代结合蛋白的性质。通过复杂的质谱分析鉴定出Syk由于其重新定位而磷酸化的推定底物，将对其进行表征，并分析其磷酸化的后果，以研究直接由Syk调节的新途径。这些研究将扩展到原代B细胞，使用来自新小鼠模型的细胞，其中Syk的活性可以使用强大的化学遗传学方法明确抑制。我们计划完成三个具体目标：1）表征酪氨酸-130磷酸化在Syk-受体和Syk-蛋白相互作用的调节中的作用，2）表征通过蛋白质组学和磷酸蛋白质组学筛选鉴定的新型Syk底物和信号传导途径，3）通过化学遗传学表征Syk在原代B细胞信号传导中的作用。采用的方法包括1）蛋白质-肽和蛋白质-蛋白质相互作用的生物化学和物理评价，2）相互作用蛋白质和激酶底物的蛋白质组学和磷酸蛋白质组学分析，3）蛋白质功能的分子和细胞研究，以及4）使用化学抑制剂阻断激酶功能 在源自表达工程激酶的遗传操作小鼠的细胞中。 公共卫生相关性：该项目的重点是一种称为Syk的酶，该酶是免疫系统的B淋巴细胞成分识别和应对传染性病原体所必需的。它的激活可以刺激应答的B淋巴细胞在数量上扩增，并发展产生抗体的能力来抵御感染。由于Syk引发增殖反应的能力也可以为白血病和淋巴瘤细胞提供增殖的途径，因此了解Syk的功能对于鉴定合适的治疗剂和药物靶点至关重要。