Mechanism of Eukaryotic Environmental Mutagenesis

描述（由申请人提供）：DMA修复和损伤容限过程对于在暴露于许多不同制剂后保护人体健康绝对至关重要。本研究的长期目标是对真核生物环境诱变的分子机制有一个详细的综合了解。在既复杂又精心控制的分子过程中，当专门的跨损伤合成（TLS）DNA聚合酶复制环境因子引起的DNA损伤时，会引入突变。拟议的研究特别强调Rev 1，它既作为其他TLS DNA聚合酶的支架，又作为聚合酶本身，是真核诱变的根源。我们将跟进我们的意外发现，S。通过研究其细胞周期控制的基础，酿酒酵母Rev 1在G2/M期的表达比在G1期和大部分S期高50倍，”这主要是转录后的;将测试有希望的候选调控基因，如UMP 1和CDC 7，将进行新调控基因的遗传筛选，并将进行实验以确定这种控制的重要性：使用生物化学和遗传学的方法，我们将继续研究Rev 1相互作用的结构和功能基础，特别是集中在Rev 1的C-末端结构域，其BRCT结构域，其泛素结合基序的相互作用。我们将调查的Rev 1聚合酶活性的功能的重要性，通过跟进我们最近的观察表明，Rev 1可能有一类同源病变，它复制得特别好。我们将探讨S. pombe DinB及其与Rev 1的关系。我们将开发一种高通量的检测方法，基于Rev 1-Rev 7相互作用的破坏，这将允许筛选真核环境诱变的抑制剂。拟议的研究将通过阐明仍知之甚少的真核跨损伤合成机制对基础科学做出非常重要的贡献。这些突变导致衰老、癌症和各种人类疾病。确定在这些诱变过程中发挥作用的其他基因将有助于解决为什么只有一些人在暴露于环境毒素时会患病的问题。TLS的小分子抑制剂可能会导致新的“抗诱变”药物，对人类健康有多种应用。

DESCRIPTION (provided by applicant): DMA repair and damage tolerance processes are absolutely critical to preserving human health following exposure to many different agents. The long term goal of this research is to develop a detailed integrated understanding of the molecular mechanisms responsible for environmental mutagenesis in eukaryotes. In molecular processes that are both complex and elaborately controlled, mutations are introduced when specialized translesion synthesis (TLS) DNA polymerases copy over DNA damage caused by environmental agents. The proposed research places a special emphasis on Rev1, which by virtue of acting both as a scaffold for other TLS DNA polymerases and as a polymerase itself, lies at the root of eukaryotic mutagenesis. We will follow up on our unanticipated finding that S. cerevisiae Rev1 is expressed 50 fold higher during G2/M than in G1 and most of S phase by investigating the basis of its cell cycle control," which is predominantly posttranscriptional; promising candidate regulatory genes such as UMP1 and CDC7 will be tested, genetic screens for new regulatory genes will be carried out, and experiments will be conducted to determine the importance Of this control: Using both biochemical and genetic approaches, we will continue to investigate the structural and functional basis of Rev1 interactions, focusing particularly on the interactions of the Rev1 C-terminal domain, its BRCT domain, and its ubiquitin-binding motifs. We will investigate the functional importance of the Rev1 polymerase activity by following up on our recent observations suggesting that Rev1 may have a class of cognate lesions it replicates particularly well. We will investigate the function and regulation of S. pombe DinB and its relationship to Rev1. We will develop a high-throughput assay, based on disruption of the Rev1-Rev7 interaction, that will allow screening for inhibitors of eukaryotic environmental mutagenesis. The proposed research will make a highly significant contribution to basic science by elucidating the still poorly understood eukaryotic translesion synthesis mechanisms responsible for most mutations. These mutations contribute to aging, cancer, and various human diseases. Identification of additional genes that play roles in these mutagenic processes will help make it possible to address the question of why only some people develop disease when exposed to an environmental toxin. Small molecule inhibitors of TLS could lead to novel "anti-mutagenesis" drugs with multiple applications to human health.