G Protein-Mediated Gene Regulation

G蛋白偶联受体检测许多不同的外部信号，包括那些调节基因的信号 表达和细胞分化。而G蛋白介导的信号转导的许多成分 通路是已知的，不同信号调节特定基因的机制仍有待研究 下定决心。途径的特异性在一定程度上由G蛋白G(α)亚基和最近的数据决定 表明这些亚基在土壤中对网生阿米巴的基因调控中起作用。的目标是 拟议的研究是为了检验G(α)亚基通过 与其他信号成分的相互作用，如MAP(丝裂原激活蛋白)激酶。至 为了实现这一目标，我们将研究盘状网柄藻在发育早期的表达情况。 在缺乏MAP激酶ERK2并表达不同野生型或嵌合型G(α)亚单位的细胞中。在……里面 此外，将使用基因筛查来确定拯救pDSC/GFP报告的抑制子突变 来自嵌合G(α)亚基抑制的基因表达。抑制子突变将是 由REMI突变创造，允许标记可能在G(阿尔法)下游发挥作用的基因 调节基因表达的亚基。将对抑制基因进行更多的表征 验证它们在调节G(α)亚基下游DSC基因表达中的功能 小路。这些研究将为控制信号转导机制提供重要的见解 真核细胞的分化。

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.