CpnA's role in cAMP signaling and the actin cytoskeleton in Dictyostelium

CpnA 在盘基网柄菌 cAMP 信号传导和肌动蛋白细胞骨架中的作用

• 批准号: 8434437
• 负责人: CYNTHIA K DAMER
• 金额: $ 31.4万
• 依托单位: CENTRAL MICHIGAN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2017-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8434437
• 关键词: Actins; Affect; Affinity Chromatography; Amoeba genus; Animal Model; Apoptosis; Applications Grants; Award; Binding; Binding Proteins; Biochemical; Biochemical Genetics; Calcium; Cell Culture Techniques; Cell Differentiation process; Cell Line; Cell physiology; Cells; Chemotaxis; Cyclic AMP; Cytoskeleton; Data; Defect; Development; Developmental Process; Dictyostelium; Dictyostelium discoideum; Disease; Eukaryotic Cell; Fruit; Genes; Genome; Goals; Grant; Heating; Human; Human Genome; Immune; Immune response; Immunoprecipitation; In Vitro; Knowledge; Lead; Life; Light; Malignant Neoplasms; Mediating; Membrane; Microfilaments; Microscopy; Molecular; Morphogenesis; Organism; Phenotype; Play; Protein Binding; Protein Family; Proteins; Proteolysis; Recruitment Activity; Regulation; Reproduction spores; Role; Signal Pathway; Signal Transduction; Signaling Molecule; Starvation; Structure; System; Techniques; Testing; Time; Tumor Necrosis Factor Receptor; Yeasts; cell motility; cell type; copine; depolymerization; design; extracellular; genetic regulatory protein; in vivo; mutant; novel; phosphoric diester hydrolase; polymerization; programs; protein function; public health relevance; receptor; research study; slug; transcription factor; yeast two hybrid system

DESCRIPTION (provided by applicant): Copines are highly conserved calcium-dependent membrane-binding proteins found in numerous diverse eukaryotic organisms. The wide array of organisms ranging from single-celled organisms to humans in which copines are found suggest that copines carry out fundamental functions important in most eukaryotic cells. A growing body of evidence indicates that copines act as regulatory proteins in signaling pathways. The model organism Dictyostelium discoideum has six copine genes (cpnA-cpnF) and provides an ideal system for studying copine function. Dictyostelium can live independently as single-celled amoebae, but when placed in starvation conditions, single amoeba signal each other to first aggregate and then differentiate into cells that form a multicellular fruiting body. This simple developmental program in Dictyostelium is widely used to study not only development, but also several basic cell processes including chemotaxis-mediated cell motility, signal transduction, programmed cell death, and cell differentiation. Previous studies showed that one of the copine proteins in Dictyostelium, CpnA, is required for normal development. The overall goal of the previous grant award was to correlate our findings on cpnA- cells during developmental processes (aim 1) and the identification of the target proteins of CpnA (aim 2) to generate more specific hypotheses about the function of CpnA. Significant progress was made on both of these specific aims and data collected during the previous grant award period has led to two new hypotheses about the function of CpnA. These two hypotheses form the two specific aims of this renewal proposal: 1) Determine if CpnA is a negative regulator of the cAMP phosphodiesterase, RegA and 2) Determine if CpnA is a negative regulator of actin filament polymerization. This grant proposal describes experiments using biochemical, genetics, and microscopy approaches to test these hypotheses. The results of these experiments will make a significant impact on this field by being the first to define a mechanistic role for a copine protein. Human copines have been implicated to play a role in cancer by regulating signaling pathways involving the ErB2 receptor and in immune responses by regulating signaling pathways involving the TNF (tumor necrosis factor) receptor. Increasing our scientific knowledge of how copines function could lead to a better understanding of cancer and immune cell-related diseases.

描述（由申请人提供）：Copines是高度保守的钙依赖性膜结合蛋白，存在于许多不同的真核生物中。从单细胞生物到人类的各种生物中都发现了仿基因，这表明仿基因在大多数真核细胞中发挥着重要的基本功能。越来越多的证据表明，复制蛋白在信号通路中起调节蛋白的作用。模式生物盘状盘齿龙（Dictyostelium disideum）具有6个copine基因（cpnA-cpnF），为研究copine功能提供了理想的系统。盘基骨柱可以作为单细胞变形虫独立生活，但当处于饥饿状态时，单个变形虫相互发出信号，首先聚集，然后分化成形成多细胞子实体的细胞。Dictyostelium的这个简单的发育程序不仅被广泛用于研究发育，而且被广泛用于研究一些基本的细胞过程，包括趋化介导的细胞运动、信号转导、细胞程序性死亡和细胞分化。先前的研究表明盘基骨柱中的一种copine蛋白CpnA是正常发育所必需的。之前的拨款的总体目标是将我们在发育过程中对cpnA-细胞的发现（目标1）与cpnA靶蛋白的鉴定（目标2）联系起来，以产生关于cpnA功能的更具体的假设。在这两个具体目标上都取得了重大进展，在之前的资助期间收集的数据导致了关于CpnA功能的两个新的假设。这两个假设构成了本更新提案的两个具体目标：1)确定CpnA是否是cAMP磷酸二酯酶RegA的负调节因子；2)确定CpnA是否是肌动蛋白丝聚合的负调节因子。这项拨款提案描述了使用生化、遗传学和显微镜方法来测试这些假设的实验。这些实验的结果将对这一领域产生重大影响，因为它们是第一个定义copine蛋白的机制作用的。人类复制因子通过调节涉及ErB2受体的信号通路在癌症中发挥作用，通过调节涉及TNF（肿瘤坏死因子）受体的信号通路在免疫反应中发挥作用。增加我们对复制细胞功能的科学知识可以更好地理解癌症和免疫细胞相关疾病。