CELL FUNCTION AND PI-5 KINASE REGULATION BY RHO

Rho GTP结合蛋白已被证明调节 肌动蛋白应激纤维和局灶性粘连，以及Rho的功能一直 与细胞运动的调节有关。我们已经证明了Rho有能力 通过调节PIP2的活性来调节细胞水平 新的PI-5激酶。我们进一步证实，Rho活动是 对于正常的细胞对生长因子的反应是必要的，并且可能是 转化细胞非锚定生长的关键成分。 Rho似乎准备成为粘合和增长的关键集成者 信号通路。 在这项研究中，我们建议确定PI-5激酶的意义 Rho对基本细胞功能的调节。我们将调查 上游调控Rho激活的机制 瞬时稳定转染法表达Rho/RAS的激活剂 突变并评估对PI-5激酶、细胞骨架等的影响 信号。我们将提纯和鉴定受调控的PI-5激酶 作者：Rho。这种蛋白质将成为验证假说的有用手段。 关于PIP2在各种细胞过程中的作用。下游 将探讨RHO调节PIP2水平的后果。 这将包括肌动蛋白聚合、生长因子的检查 响应和磷脂酶D活性的调节。在漫长的岁月里 我们的目标是了解细胞是如何工作的，尤其是 是由世卫组织的GTP结合蛋白控制的 一家人。目前的研究应该会带来对该建筑群的新见解 细胞生长、转化和黏附之间的关系，与 与肿瘤的发展和所涉及的事件特别相关 在肿瘤转移中的作用。

The Rho GTP-binding proteins have been shown to regulate the assembly of actin stress fibers and focal adhesions, and Rho function has been implicated in regulation of cell motility. We have shown that Rho is able to regulate the cellular levels of PIP2 by modulating the activity of a novel PI-5 kinase. We have further established that Rho activity is necessary for normal cellular responsiveness to growth factors, and may be a critical component of anchorage-independent growth of transformed cells. Rho appears to be poised as a critical integrator of adhesion and growth signaling pathways. We propose in this study to determine the significance of PI-5 kinase regulation by Rho for basic cellular function. We will investigate the mechanisms involved in the control of Rho activation by upstream activators using transient and stable transfection to express Rho/Ras mutants and evaluate effects on PI-5 kinase, the cytoskeleton, and other signals. We will purify and characterize the PI-5 kinase that is regulated by Rho. This protein will serve as a useful means to validate hypotheses about the role of PIP2 in various cellular processes. The downstream consequences of the regulation of PIP2 levels by Rho will be explored. This will include examination of actin polymerization, growth factor responsiveness, and regulation of phospholipase D activity. In the long term, our goal is to understand how cellular function, particularly that of immune cells, is controlled by the GTP-binding proteins of the who family. The current studies should lead to new insights into the complex relationship between cell growth, transformation, and adhesion, with particular relevance to the development of tumors and the events involved in tumor metastasis.