Role of Shc and LRP1 in Transformation by v-Src

描述（由申请人提供）：v-Src作为模型癌基因已研究超过25年，但仍不清楚哪些底物对其转化细胞的能力起关键作用。我们最近确定LRPI作为一个Shc相关的蛋白在v-Src转化细胞。酪氨酸磷酸化后，LRP 1与Shc和可能的其他信号蛋白结合。这些观察结果产生了一种模型，其中Shc通过与LRPI结合而被募集到血浆中。Shc被认为是在细胞膜上参与Ras的激活。该基金旨在了解Shc和LRP 1在v-Src细胞转化中的作用。此外，我们建议确定新的V-Src基板。鉴定在细胞转化过程中发挥重要作用的底物是重要的，因为它将导致对这一过程的新见解。此外，这些底物提供了干预的目标。为了找出Shc或LRP 1在通过v-Src转化期间是否重要，我们将分析v-Src转化Shc缺陷型和LRP 1缺陷型细胞的能力。为了研究Src如何选择LRP 1作为底物，我们将突变Src中的不同结构域，并询问它们中哪些是LRP 1酪氨酸磷酸化所必需的。初步证据表明Shc与一种或多种LRP 1亚型结合。我们提出实验来确定这些异构体。最后，我们提出纯化和鉴定新的v-Src底物。

DESCRIPTION (provided by applicant): v-Src has been studied as a model oncogene for over 25 years and it is still unclear which substrates contribute critically to its ability to tranform cells. We recently identified LRPI as a Shc associated protein in v-Src transformed cells. Upon tyrosine phosphorylation LRP1 associates with Shc and possibly other signaling proteins. These observations led to a model in which Shc is recruited to the plasma by binding to LRPI. It is at the membrane that Shc is thought to be involved in Ras activation. This grant is aimed at understanding the role of Shc and LRP1 in cellular transformation by v-Src. In addition, we propose to identify novel v-Src substrates. Identification of substrates that play an important role during cellular transformation is important because it will lead to new insights into this process. In addition these substrates provide targets for intervention. To find out whether either Shc or LRP1 are important during transformation by v-Src we will analyze the ability of v-Src to transform Shc-deficient and LRPl-deficient cells. To investigate how Src selects LRP1 as a substrate, we will mutate the different domains in Src and ask which of them are essential for the tyrosine phosphorylation of LRP1. Preliminary evidence suggests that Shc binds to one or more LRP1 isoforms. We propose experiments to identify those isoforms. Finally we propose purify and identify novel v-Src substrates.