G Protein-Mediated Gene Regulation

G蛋白介导的基因调控

• 批准号: 6898083
• 负责人: JEFFREY A HADWIGER
• 金额: $ 22.11万
• 依托单位: OKLAHOMA STATE UNIVERSITY STILLWATER
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-01 至 2009-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6898083
• 关键词: Dictyostelium; G protein; biological signal transduction; cell differentiation; cell surface receptors; flow cytometry; gene expression; genetic regulation; green fluorescent proteins; mitogen activated protein kinase; protein protein interaction; protozoal genetics; reporter genes; site directed mutagenesis; yeast two hybrid system

DESCRIPTION (provided by applicant): G protein-coupled receptors detect many different external signals including ones that regulate gene expression and cellular differentiation. While many components of G protein-mediated signal transduction pathways are known, the mechanisms by which different signals regulate specific genes remains to be determined. Pathway specificity is, in part, determined by the G protein G (alpha) subunits, and recent data indicate these subunits play a role in gene regulation in the soil amoebae Dictyostelium. The goal of the proposed research is to test the hypothesis that G (alpha) subunits regulate gene expression through interactions with other signaling components, such as MAP (mitogen-activated protein) kinases. To achieve this goal, the early developmental expression of discoidin (Dsc) in Dictyostelium will be examined in cells lacking the MAP kinase Erk2 and expressing different wild-type or chimeric G (alpha) subunits. In addition, a genetic screen will be used to identify suppressor mutations that rescue pDSC/GFP reporter gene expression from the repression of a chimeric G (alpha) subunit. The suppressor mutations will be created by REMI mutagenesis, allowing genes to be tagged that might function downstream of G (alpha) subunits to regulate gene expression. Additional characterization of suppressor genes will be conducted to verify their function regulating DSC gene expression downstream of G (alpha) subunits in these signaling pathways. These studies will provide significant insights into the signaling mechanisms that control the differentiation of eukaryotic cells.

描述(申请人提供)：G蛋白偶联受体检测许多不同的外部信号，包括那些调节基因表达和细胞分化的信号。虽然已知G蛋白介导的信号转导通路的许多组成部分，但不同信号调节特定基因的机制仍有待确定。途径的特异性在一定程度上是由G蛋白G(α)亚基决定的，最近的数据表明这些亚基在土壤中的阿米巴Dictyostelius中起着基因调控的作用。这项拟议研究的目的是检验G(α)亚基通过与其他信号成分(如MAP(丝裂原激活蛋白)激酶)相互作用来调节基因表达的假设。为了实现这一目标，将在缺乏MAP激酶ERK2并表达不同野生型或嵌合型G(α)亚基的细胞中检测盘状结构蛋白(DSC)在Dictyostelials中的早期发育表达。此外，基因筛查将被用来识别抑制突变，这些突变将pDSC/GFP报告基因的表达从嵌合G(α)亚单位的抑制中拯救出来。抑制突变将通过REMI突变产生，允许标记可能在G(α)亚基下游发挥作用的基因，以调节基因表达。还将对抑制基因进行进一步的鉴定，以验证它们在这些信号通路中调节G(α)亚基下游DSC基因表达的功能。这些研究将为控制真核细胞分化的信号机制提供重要的见解。