Mechanistic insights into translesion synthesis-dependent genome instability

基因组不稳定性，其特征是DNA突变和其他遗传因素的形成增加。 修饰，是多种人类疾病的致病因素，包括癌症、感染性疾病、 疾病和神经退行性疾病。跨损伤合成（TLS）途径，通过 它的低保真度聚合酶，通过绕过DNA损伤和填充后， 复制DNA缺口;主要由REV 1聚合酶协调的过程。因此，TLS 和REV 1是基因组不稳定性的重要组成部分， 突变，然后转化为新的，往往是有害的细胞功能。最近的发现 从我的实验室挑战这个一维模型，并有深远的影响， 了解人类疾病，并可能提供开发新疗法的机会。我们有 发现REV 1聚合酶在控制基因组不稳定性方面的作用比 最初的想法。REV 1调节自噬、代谢过程、有丝分裂保真度， 通过再复制产生复制应激。我们有证据表明，这些额外的，以前 REV 1调节自噬与衰老的细胞代谢选择的未被认识的作用 对不同类型的DNA损伤作出反应，因此可能控制细胞死亡机制。 此外，我们的初步数据出乎意料地表明REV 1直接调节自噬， 有丝分裂和再复制蛋白质。虽然这些早期的结果是诱人的， 这些问题-REV 1如何控制细胞代谢和参与有丝分裂保真度， 复制是一个黑盒子。这里提出的工作将系统地梳理出 REV 1聚合酶新作用的机制基础。本提案的目标是 确定REV 1行使这些新承认的功能的机制， 利用新颖和尖端的工具来提出基本的生物学问题。成功完成 我们提出的研究将重新定义REV 1的作用，从一种容易出错的聚合酶， 参与TLS DNA诱变过程，形成一个多维度调节因子， 疾病的发生或发展不仅通过使DNA突变，而且通过控制细胞 代谢、有丝分裂保真度和再复制，对基因组不稳定过程至关重要。

Genome instability, characterized by increased formation of DNA mutations and other genetic modifications, is a causative factor in multiple human diseases including cancer, infectious diseases, and neurodegenerative disorders. The translesion synthesis (TLS) pathway, by means of its low fidelity polymerases, causes mutagenesis by bypassing DNA damages and filling post- replicative DNA gaps; a process principally orchestrated by the REV1 polymerase. Thus, TLS and REV1 are essential components of genome instability that drive the formation of new mutations that then translate into new, and often deleterious cellular functions. Recent discoveries from my laboratory challenge this one-dimensional model and have profound implications for understanding human disease and may offer opportunities to develop new therapeutics. We have discovered that the REV1 polymerase has a broader role in controlling genome instability than originally thought. REV1 regulates autophagy, metabolic processes, mitosis fidelity, and replication stress through rereplication. We have evidence that these additional, previously unrecognized roles of REV1 regulate cellular metabolic choices of autophagy versus senescence in response to different types of DNA damages and as such might control cell death mechanisms. Furthermore, our preliminary data unexpectedly showed that REV1 directly regulates autophagy, mitosis, and rereplication proteins. While these early results are enticing, the fundamentals of these discoveries—how REV1 controls cellular metabolism and participates in mitosis fidelity and rereplication are a black box. The work proposed here will systematically tease apart the mechanistic basis of the new roles of the REV1 polymerase. The goals of this proposal are to determine the mechanisms by which REV1 exercises these newly recognized functions by utilizing novel and cutting-edge tools to ask basic biological questions. Successful completion of our proposed studies will redefine the role of REV1, from an error-prone polymerase that participates in the TLS DNA mutagenesis process to a multi-dimensional regulator that controls disease onset or progression by not only making mutations in DNA, but also by controlling cellular metabolism, mitotic fidelity, and rereplication, central to the genome instability process.