Regulation and Localization of Mismatch Repair Proteins

主要研究者/项目负责人（最后，第一，中间）：Haye，Joanna，Elizabeth 摘要： DNA错配修复（MMR）是一个高度保守的过程。功能性MMR通路对于以下方面至关重要： 维持基因组完整性; MMR的丧失导致高等真核生物的基因组不稳定性和癌症。为 例如，MMR基因的缺陷导致Lynch综合征，这是一种常见的遗传性癌症综合征， 结肠、子宫内膜、卵巢、小肠、肝胆道、上尿路的早发性癌症 以及其他组织。在我们最近的出版物中，我们表明在酵母中， 转录（也称为Not 4）或一般控制非去阻遏蛋白5（Gcn 5）调节 Msh 2是MMR的主要组成部分。Gcn 5的缺失显著降低了Msh 2，而删除Not 4则稳定了Msh 2。 功能性Msh 2。Not 4和Gcn 5是分别使各种蛋白质泛素化和乙酰化的蛋白质。我们 假设Not 4和Gcn 5修饰酵母MutSα（由Ms 2和Msh 6组成），且修饰 影响复合物的稳定性。利用酿酒酵母（Saccharomyces cerevisiae，S.酿酒），第一个目标， 这项研究旨在确定Gcn 5和Not 4在调节主要错配中的作用。 识别复合物MutSα。我们以前的实验也表明，酵母MutS跟踪与 DNA复制过程中的复制机制。人类MutSα通过特异性组蛋白被募集到染色质中 通过结合PCNA，DNA聚合酶的持续合成能力， 因子然而，招募人MutSα的修饰在酵母中不被利用。酵母MutSα是如何 被招募到染色质中仍然是难以捉摸的。本研究的第二个目的是确定后- MutSα向染色质募集的翻译修饰。 PHS 398（Rev. 5/01）页

Principal Investigator/Program Director (Last, first, middle): Haye, Joanna, Elizabeth Abstract: DNA mismatch repair (MMR) is a highly conserved process. A functional MMR pathway is essential for maintaining genome integrity; loss of MMR results in genome instability and cancer in higher eukaryotes. For example, defects in MMR genes result in Lynch Syndrome, a common hereditary cancer syndrome resulting in early onset cancers of the colon, endometrium, ovaries, small intestine, hepatobiliary tract, upper urinary tract as well as other tissues. In our most recent publication, we showed that in yeast, deletion of Modulator of Transcription (also known as Not4) or General Control Nonderepressible 5 (Gcn5) modulate the levels of Msh2, a major MMR component. Loss of Gcn5 significantly decreases Msh2, whereas deleting Not4 stabilizes functional Msh2. Not4 and Gcn5 are proteins that ubiquitylate and acetylate various proteins respectively. We hypothesize that Not4 and Gcn5 modify yeast MutSα (comprised of Ms2 and Msh6) and that the modifications affect the stability of the complex. Using the yeast Saccharomyces cerevisiae (S. cerevisiae), the first aim of the proposed research is to establish the role of Gcn5 and Not4 in the regulation of the major mismatch recognition complex MutSα. Our previous experiments have also shown that yeast MutS tracks with the replication machinery during DNA replication. Human MutSα is recruited to chromatin through specific histone modifications and interacts with the replication machinery by binding PCNA, the DNA polymerase processivity factor. However, the modifications that recruit human MutSα are not utilized in yeast. How yeast MutSα is recruited to chromatin remains elusive. The second aim of this research is to determine the role of post- translational modifications in MutSα recruitment to chromatin. PHS398 (Rev. 5/01) Page Continuation Format Page