ETHANOL AND INTRACELLULAR SIGNAL TRANSDUCTION

这是KO-5高级科学家奖的提案 候选人拉斐尔·鲁宾医学博士是系里的教授。托马斯杰斐逊大学病理学系。 鲁宾博士有一个长期的酒精研究计划，研究酒精对细胞内信号传导过程的影响。 这些研究在托马斯杰斐逊大学酒精研究中心的环境中进行。 他连续15年获得NIAAA的RO-1和职业发展奖。 KO-5奖将使候选人能够将大部分时间用于酒精研究，从而大大减轻行政和临床责任。 鲁宾博士目前研究的总体重点是乙醇对酪氨酸激酶受体信号传导的影响。 乙醇抑制IGF-IR酪氨酸自磷酸化和随后的信号传导事件，导致细胞增殖抑制和凋亡增强。 该提案回顾了目前资助的旨在评估乙醇与IGF-I信号通路相互作用的分子和功能方面的研究。 假设乙醇干扰IGF-IR胞质β结构域内的酪氨酸激酶活性。研究将确定乙醇对体外纯化IGF-IR酪氨酸激酶活性的影响，以及对特定酪氨酸磷酸化的影响。IGF-IR β结构域上的乙醇敏感位点将通过定点诱变进行功能定位。 将在鼠成纤维细胞和神经胶质细胞系中评估乙醇-IGF-IR相互作用对细胞凋亡的影响。 乙醇促进细胞凋亡可能与IGF-IR及其近端信号介质的表达有关。 一种新的功能表达cDNA克隆方法将用于确定乙醇对IGF-I诱导的存活基因表达的影响。 另外的研究也证明了小脑颗粒细胞中NMDA和IRS-1信号通路之间的串扰通路。 未来的研究旨在进一步评估NMDA诱导的IRS-1作用的机制，并评估IGF-IR在NMDA神经保护中的作用。

This is a proposal for a KO-5 Senior Scientist Award. The candidate, Raphael Rubin, M.D., is a Professor in the Dept. of Pathology, Thomas Jefferson University. Dr. Rubin has a longstanding alcohol research program that investigates the effects of alcohol on intracellular signaling processes. These studies have been performed within the environment of the Thomas Jefferson University Alcohol Research Center. He has been funded continuously by the NIAAA for 15 years with RO-1 and career development awards. The KO-5 award would allow the candidate to dedicate most of his time to alcohol research by providing substantial relief from administrative and clinical responsibilities. The overall focus of Dr. Rubin's current studies is the effect of ethanol on tyrosine kinase receptor signaling. Ethanol inhibits IGF-IR tryosine autophosphorylation and subsequent signaling events resulting in the inhibited cell proliferation and enhancement of apoptosis. This proposal reviews currently funded studies designed to assess molecular and functional aspects of the interaction of ethanol with the IGF-I signaling pathway. It is hypothesized that ethanol interferes with the tyrosine kinase activity residing within the cytoplasmic beta domain of the IGF-IR. Studies will determine the effect of ethanol on the tyrosine kinase activity of purified IGF-IR in vitro, and on the phosphorylation of specific tyrosines. Ethanol-sensitive sites on the IGF-IR beta domain will be functionally mapped by site-directed mutagenesis. The consequences of the ethanol-IGF-IR interaction for apoptosis will be assessed in murine fibroblasts and neuroglial cell lines. The enhancement of apoptosis by ethanol will be correlated with the expression of IGF-IR and its proximal signal mediators. A novel functional expression cDNA cloning approach will be used to determine the effect of ethanol on IGF-I-inducible survival gene expression. Additional studies have also demonstrated cross-talk pathways in cerebellar granule cells between NMDA and IRS-1 signaling pathways. Future studies are designed to further assess the mechanism of NMDA-induced IRS-1 action, and to evaluate the role of the IGF-IR in NMDA neuroprotection.