UBIQUITINATION LENS PROLIFERATION/DIFFERENTIATION

描述（改编自申请人摘要）：在形成和生长期间 透镜细胞必须执行增殖、有丝分裂退出和 分化在大多数细胞中，为了从增殖发展到 分化的表型，许多调节和结构蛋白（即p57） 通过泛素（Ub）蛋白水解途径去除。UB的功能 蛋白水解途径存在于所有真核细胞中， 几乎细胞调节的每个方面，包括细胞周期进程 与分化，胁迫反应，DNA修复，信号转导，基因 原癌基因调控，细胞重塑，抗原 呈现和去除受损的蛋白质。我们已经展示了 在透镜细胞中存在功能性Ub通路并收集初步数据 这与调节从有丝分裂到有丝分裂的过程的Ub途径一致。 分化表型然而，Ub通路在调节 细胞周期和分化在透镜一直是焦点只有三个 出版物，并且没有特定的底物的Ub依赖性途径一直是未知的。 在整个透镜单元系统中识别。根据我们最初的出版物， 初步数据和其他细胞类型的数据，我们假设Ub 蛋白水解途径，特别是泛素缀合酶Ubc 2、3和4， 以允许透镜细胞从增殖型转变为 分化的细胞类型我们将使用透镜外植体来检验这一假设， in vivo.我们的长期目标是识别和展示 Ub蛋白水解途径的组分，包括调节 透镜细胞增殖和分化。调查人员有经验 在这项研究所需的所有技术中。此外，本发明还提供了一种方法， 他们将得到1）Borras和Zelenka医生对透镜感染的指导 细胞与腺病毒，和2）显性阴性结构的贡献 所有可用的Ubc和Ubc敲除小鼠的数据。以来 只有有限的文献关于Ub途径在 哺乳动物系统，这项工作将是感兴趣的所有学者的哺乳动物 发展和分化。泰勒博士的小组是一个主要贡献者， 关于Ub通路在细胞应激反应中的功能的文献。

DESCRIPTION (Adapted from applicant's abstract): During formation and growth lens cells must execute a program of proliferation, mitotic withdrawal and differentiation. In most cells, in order to progress from proliferative to differentiated phenotypes, many regulatory and structural proteins (i.e. p57) are removed via the ubiquitin (Ub) proteolytic pathway. Function of the Ub proteolytic pathway is found in all eucaryotic cells and is implicated in virtually every facet of cellular regulation, including cell cycle progression and differentiation, the stress response, DNA repair, signal transduction, gene regulation, control of protooncogenes, cellular remodeling, antigen presentation, and removal of damaged proteins. We have demonstrated the presence of a functional Ub pathway in lens cells and gathered preliminary data which is consistent with the Ub pathway regulating progress from a mitotic to a differentiated phenotype. However, the role of the Ub pathway in regulation of cell cycle and differentiation in lens has been the focus of only three publications, and no specific substrate for the Ub dependent pathway has been identified in a whole lens cell system. Based on our initial publications, preliminary data and data from other cell types, we hypothesize that the Ub proteolytic pathway, particularly ubiquitin conjugating enzymes Ubc2,3,and 4, are required to allow transition of lens cells from a proliferative to a differentiated cell type. We will test this hypothesis using lens explants and in vivo. Our long-term goals are to identify and demonstrate the function of components of the Ub proteolytic pathway, including substrates, which regulate lens cell proliferation and differentiation. The investigators have experience in all of the techniques which are required for this research. In addition, they will have 1) the guidance of Drs. Borras and Zelenka for infection of lens cells with adenovirus, and 2) the contributions of dominant negative constructs of all available Ubc and Ubc knockout mice from Drs. Pagano and Wing. Since there is only a limited literature regarding functions of the Ub pathway in mammalian systems, this work will be of interest to all scholars of mammalian development and differentiation. Dr. Taylor's group is a major contributor to the literature regarding Ub pathway functions in response to cellular stress.