Function and Regulation of DNA Damage Response Genes

描述（由申请人提供）：所有生物体的生存取决于DNA从一个细胞到其子细胞的忠实传递。细胞通过阻止细胞周期和诱导DNA修复基因的转录来响应DNA损伤。Crt 1蛋白被认为是DNA损伤诱导的核糖核苷酸还原酶（RNR）基因转录的关键调节因子。该研究计划的广泛，长期目标是利用分子遗传学和生物化学的现代方法来了解细胞对DNA损伤反应的机制。本项目的重点是Crtl的功能研究，并将其与DNA损伤反应的调控联系起来。该提议还试图研究涉及DNA损伤诱导转录的CRT 1非依赖性机制。本研究的具体目的是：（1）研究上游检查点激酶对Crt 1活性的调控，以了解Crt 1介导的DNA损伤反应的负反馈机制。(2)为了表征Crt 1和一般阻遏物复合物Ssn 6/Tup 1之间的相互作用，以响应DNA损伤，从而理解DNA损伤检查点如何控制从阻遏状态到诱导状态的转换。(3)确定参与DNA损伤诱导的RNR基因转录的CRT 1非依赖性机制，最终目的是了解由DNA损伤检查点控制的不同调控途径之间的相互作用。DNA损伤反应的失败导致基因组不稳定性和癌症易感性。因此，这项研究将有助于加深对DNA损伤和修复的复杂生物学的理解。这些研究对于指导我们针对癌症诊断、预防和治疗的DNA损伤反应过程的努力也至关重要。

DESCRIPTION (provided by applicant): The survival of all organisms depends on the faithful transmission of DNA from one cell to its daughter cell. Cells respond to DNA damage by arresting the cell cycle and inducing the transcription of DNA repair genes. The Crt 1 protein has been identified as a key regulator of DNA damage-induced transcription of the genes encoding ribonucleotide reductase (RNR). The broad, long-term objective of this research program is to use modem methods in molecular genetics and biochemistry to understand the mechanisms underlying cellular response to DNA damage. The focus of this project is on the functional studies of Crtl, and to relate this understanding to the regulation of DNA damage response. This proposal also seeks to investigate CRT1-independent mechanism(s) involved in DNA damage-induced transcription. Specific aims of the proposed research are: (1) To characterize the regulation of Crt 1 activities by the upstream checkpoint kinases in order to understand the negative feedback mechanism of the CRTl-mediated DNA damage response. (2) To characterize the interactions between Crtl and the general repressor complex Ssn6/Tup 1 in response to DNA damage in order to understand how the DNA damage checkpoint controls the switch from the repressed state to the induced state. (3) To determine CRTl-independent mechanism(s) involved in the DNA damage-induced transcription of the RNR genes with the ultimate aim of understanding the interplay among different regulatory pathways controlled by the DNA damage checkpoint. Failure of DNA damage response results in genomic instability and cancer predisposition. As a result, this research will contribute to an increased understanding of the complex biology of DNA damage and repair. These studies will also be critical in guiding our efforts to target the DNA damage response process for cancer diagnosis, prevention, and treatment.