Adhesive Signaling by Platelet Integrins

血小板整合素的粘附信号传导

基本信息

批准号：
8623141
负责人：
SANFORD J SHATTIL
金额：
$ 37.98万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN DIEGO
依托单位国家：
美国
项目类别：
财政年份：
1996
资助国家：
美国
起止时间：
1996-07-01 至 2016-02-29
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8623141
关键词：
Address Adhesives Affinity Agonist Antibodies Apoptosis Avidity Biochemical Biological Assay Biological Models Biology Blood Platelet Disorders Blood Platelets Blood Vessels Breast Cancer Cell Cancer cell line Cell Proliferation Cell model Cell-Cell Adhesion Cells Chinese Hamster Ovary Cell Co-Immunoprecipitations Data Development Diagnostic Distant Embryo Exhibits Extravasation Fluorescence Resonance Energy Transfer Funding Future Gene Targeting Guanosine Triphosphate Phosphohydrolases Hemostatic function Hepatic Human Imaging Techniques In Situ Injury Integrin-mediated Cell Adhesion Pathway Integrins Label Lead Learning Ligand Binding Ligands Ligation Location Malignant Neoplasms Mediating Megakaryocytes Metastatic Neoplasm to the Liver Microscopy Modeling Molecular Molecular Conformation Monitor Mus Nature Neoplasm Metastasis Neoplasms Organ Physiological Platelet Activation Process Proteins Receptor Activation Regulation Reverse Transcriptase Polymerase Chain Reaction Role Signal Transduction System Talin Techniques Testing Therapeutic Thrombosis Tumor Suppressor Genes Tumor Suppressor Proteins Up-Regulation Zebrafish adapter protein adhesion receptor base cancer cell cellular engineering genetic regulatory protein human DLC1 protein insight melanoma mimetics neoplastic cell research study response small hairpin RNA src-Family Kinases tumor progression tumorigenesis two-photon

项目摘要

DESCRIPTION (provided by applicant): Integrins mediate cell adhesion and signaling during physiological responses to vascular injury, as exemplified by the requirement for platelet ¿IIb¿3 in hemostasis. Furthermore, evidence indicates that integrins may function abnormally in pathological circumstances, such as arterial thrombosis and neoplasia. A key regulatory step in integrin function is receptor activation, manifest by conversion from a low- to a high-affinity conformational state, and from an unclustered to a clustered, high-avidity state. Integrin activation is regulated by "inside-out" signals that are triggered by cellular agonists, although te precise nature of these signals remains incompletely understood. The long-term objectives of this proposal are to 1) fully understand the molecular basis of inside-out ¿IIb¿3 signaling in platelets; and 2) extend these fundamental concepts to integrins in human cancer cells, since these integrins have been implicated in tumor progression, including the metastatic cascade. Two specific aims will address major unresolved questions pertaining to these objectives. Aim 1 will test the hypothesis that a specific molecular adapter protein, ADAP, interacts functionally if not physically with one or more recently identified integrin-proximal regulatory proteins (e.g., talin, kindlin), to activate ¿IIb¿3 in response to platelet agonists. Accordingly, biochemical and advanced imaging techniques will be used to determine whether and how ADAP interacts with such integrin-proximal regulators in platelets, in gene-targeted primary murine megakaryocytes, and in model cells engineered to recapitulate ¿IIb¿3 activation. These experimental systems will also be used to assess the role of ADAP in promoting changes in ¿IIb¿3 clustering as a mechanism of ¿IIb¿3 activation complementary to affinity modulation. Aim 2 will test the hypothesis that activation of ¿1 integrins is required for tumor cell extravasation from blood vessels and for the development of metastatic foci. Preliminary data indicate the presence of activated ¿1 integrins in human cancers. Therefore, human melanoma and breast cancer cell lines and a well-characterized vertebrate experimental metastasis model system will be used to address which ¿1 integrins must become activated to promote metastasis, whether specific integrin-interacting proteins such as talin, kindlin and Src family kinases are involved, and whether deletion of a specific tumor suppressor gene, DLC-1, promotes metastasis by activating ¿1 integrins. The proposed studies will establish common and unique mechanisms of integrin activation in physiological and pathological circumstances, with diagnostic and therapeutic implications for vascular biology and beyond.

描述（通过应用程序提供）：整联蛋白在血管损伤的物理反应过程中介导细胞粘合剂和信号传导，这是止血中血小板的需求的例证。此外，证据表明整联蛋白在病理状况（例如动脉血栓形成和肿瘤）中可能异常起作用。整联蛋白功能的关键调节步骤是受体激活，这是通过从低亲和力构象状态以及从群集到群集的高避免性状态的转化来表现出来的。整联蛋白的激活受到细胞激动剂触发的“内部”信号的调节，尽管这些信号的精确性尚未完全理解。该提议的长期目标是1）完全了解血小板中内而外的3个信号的分子基础； 2）将这些基本概念扩展到人类癌细胞中整联蛋白，因为这些整联蛋白已在肿瘤进展中实施，包括转移性级联反应。两个具体的目标将解决与这些目标有关的主要未解决问题。 AIM 1将检验以下假设：如果没有一个或多个最近确定的整联蛋白 - 羟基调节蛋白（例如，塔林，金林），以响应血小板激动剂来激活»iib歌。彼此之间，将使用生化和先进的成像技术来确定ADAP在血小板，基因靶向的原代鼠大型巨核细胞和模型细胞中以及设计用于重新识别€iib¿3激活的模型细胞中是否与这种整联蛋白 - 透明度调节剂相互作用。这些实验系统还将用于评估ADAP在促进IIB的变化中的作用。3聚类作为„ IIB字的机制3激活对亲和力调制的完整性。 AIM 2将检验以下假设：肿瘤细胞从血管中渗出和转移灶的发展需要1个整联蛋白的激活。初步数据表明在人类癌症中存在激活的1整合素。 Therefore, human melanoma and breast cancer cell lines and a well-characterized vertebrate experimental metastasis model system will be used to address which ¿ 1 integrins must become activated to promote metastasis, whether specific integrin-interacting proteins such as talin, kindlin and Src family kindses are involved, and whether deletion of a specific tumor suppressor gene, DLC-1, promotes metastasis by activating ¿ 1 integrins.拟议的研究将在物理和病理环境中建立整合素激活的共同和独特的机制，并具有对血管生物学及其他地区的诊断和治疗意义。