UBIQUITIN AND YEAST CD34 GENE FUNCTION

酿酒酵母Cdc34蛋白，一种泛素结合蛋白 酶，可以进行autoubiquitination。反应产物是 多泛素化Cdc34蛋白。多遍在蛋白链的连接 通常是选择性降解的信号， 蛋白Cdc34蛋白是否是这种情况是本研究的主题。 提议的研究。我们建议确定自来水厂 然后通过体外诱变改变这些位点， 产生自泛素化缺陷突变体。我们将表达这些 酿酒酵母中的突变体，以确定是否 自泛素化作用靶向Cdc34蛋白进行降解， 这种退化在控制可获得性方面是否重要， Cdc34蛋白在细胞周期中的作用。最后，我们将进一步定义 CDC34的生化作用，通过鉴定和表征蛋白质， 与Cdc34蛋白质相互作用，或者作为多蛋白质 复合物或作为Cdc34依赖性泛素化的底物。这些 研究将导致对泛素化作用的重要见解 控制细胞生长。

Cdc34 protein of Saccharomyces cerevisiae, a ubiquitin conjugating enzyme, can undergo autoubiquitination. The reaction product is a multiubiquitinated Cdc34 protein. Attachment of a multiubiquitin chain to a protein is usually a signal for selective degradation of that protein. Whether this is the case for Cdc34 protein is a subject of the proposed research. We propose to identify the autoubiquitination sites in Cdc34 protein and then alter these sites by in vitro mutagenesis to generate autoubiquitination-defective mutants. We will then express these mutants in Saccharomyces cerevisiae to determine whether autoubiquitination serves to target Cdc34 protein for degradation and whether such degradation is important in controlling the availability of Cdc34 protein during the cell cycle. Finally, we will further define the biochemical role of CDC34 by identifying and characterizing proteins that interact with Cdc34 protein, either as participants in a multiprotein complex or as substrates for Cdc34-dependent ubiquitination. These studies will lead to important insights into the role of ubiquitination in the control of cell growth.