The SMC5/6 Complex - DNA Damage Response Regulation Ensures Meiotic Fidelity

项目概要/摘要： 我们知道减数分裂期间DNA损伤反应受到干扰会导致不育，流产或 遗传缺陷然而，我们对DNA损伤反应的调节知之甚少， 减数分裂我的初步数据表明SMC 5/6复合物是介导DNA损伤所必需的 减数分裂细胞周期进程中的反应。因为SMC 5/6复合物对于细胞活力是必需的， 在哺乳动物中的体内实验尚未进行，我们对SMC 5/6在哺乳动物中的功能的理解是， 哺乳动物有限。我正在制造一种Smc 5的生殖细胞特异性突变， SMC 5/6基因Eid 3.这些突变体将使我能够对SMC 5/6进行首次全面研究 减数分裂中的复杂功能（Aim 1）。EID 3是SMC 5/6复合物的睾丸特异性Kleisin亚基。然而，在这方面， 体细胞Kleisin SMC 5/6亚基NSE 4也在睾丸内表达。因此，有两个 SMC 5/6复合物存在于睾丸内，SMC 5/6 NSE 4和SMC 5/6 EID 3。我会找出相似之处， 两种复合物之间的差异（目标2）。我已经证实SMC 5/6复合物与 BAT 3-EP 300复合物。BAT 3-EP 300复合物是激活TRP 53介导的DNA所必需的 损伤响应根据SMC 5/6和BAT 3之间的蛋白质相互作用网络， 在EP 300复合物中，SMC 5/6作为DNA损伤反应途径的关键组分出现， 调节TRP 53乙酰化。在目标3中，我将详细评估 EID 3对BAT 3-EP 300的拮抗作用，以及EID 3对BAT 3-EP 300的拮抗作用的生化分析。 EP 300介导的TRP 53乙酰化。我对K99/R 00奖的假设是，SMC 5/6作为 修复/监视复合物协调DNA修复和TRP 53介导的DNA损伤 反应这一功能确保了减数分裂前期向中期I过渡时的保真度。

Project Summary/Abstract: We know a perturbed DNA damage response during meiosis will result in infertility, pregnancy loss or genetic defects. However, we know very little about the regulation of the DNA damage response during meiosis. My preliminary data implies that the SMC5/6 complex is required to mediate the DNA damage response during meiotic cell cycle progression. Because the SMC5/6 complex is essential for cell viability, in vivo experiments in mammals have not been performed and our understanding of the function of SMC5/6 in mammals is limited. I am creating a germ cell-specific mutation of Smc5 and mutating the testis specific SMC5/6 gene Eid3. These mutants will enable me to perform the first comprehensive studies of SMC5/6 complex function in meiosis (Aim1). EID3 is a testis-specific kleisin subunit of the SMC5/6 complex. However, the somatic cell kleisin SMC5/6 subunit, NSE4, is also expressed within the testis. Therefore, there are two SMC5/6 complexes present within the testis, SMC5/6NSE4 and SMC5/6EID3. I will determine the similarities and differences between the two complexes (Aim 2). I have confirmed that the SMC5/6 complex interacts with the BAT3-EP300 complex. The BAT3-EP300 complex is required for the activation of a TRP53-mediated DNA damage response. According to the protein interaction network developed between the SMC5/6 and the BAT3- EP300 complexes, SMC5/6 emerges as a key component of the DNA damage response pathway, by regulating TRP53 acetylation. In Aim 3, I will conduct a detailed assessment of the interaction between SMC5/6 and BAT3-EP300, together with biochemical analysis of the antagonistic function of EID3 on BAT3- EP300-mediated TRP53 acetylation. I approach the K99/R00 award with the hypothesis that SMC5/6 acts as a repair/surveillance complex coordinating DNA repair and the TRP53-mediated DNA damage response. This function ensures fidelity at the prophase to metaphase I transition of meiosis.