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

项目摘要/摘要： 我们知道在减数分裂过程中受到干扰的DNA损伤反应会导致不孕、妊娠丢失或 基因缺陷。然而，我们对DNA损伤反应的调控知之甚少。 减数分裂。我的初步数据表明，SMC5/6复合体是介导DNA损伤所必需的 减数分裂细胞周期进程中的反应。因为SMC5/6复合体对细胞存活是必不可少的，在 在哺乳动物身上的活体实验还没有进行，我们对SMC5/6在 哺乳动物是有限的。我正在创造一种Smc5的生殖细胞特异性突变，并使睾丸特异性突变 SMC5/6基因Eid3。这些突变体将使我能够对SMC5/6进行第一次全面的研究 减数分裂中的复杂功能(Aim1)。EID3是SMC5/6复合体中睾丸特异的Kleisin亚基。然而， 体细胞Kleisin SMC5/6亚单位NSE4也在睾丸内表达。因此，有两个 SMC5/6复合体存在于睾丸内，即SMC5/6NSE4和SMC5/6EID3。我将确定它们的相似之处和 两个复合体之间的差异(目标2)。我已经证实SMC5/6复合体与 BAT3-EP300复合体。BAT3-EP300复合体是激活TrP53介导的DNA所必需的 损坏反应。根据SMC5/6和BAT3之间发展的蛋白质相互作用网络- EP300复合体，SMC5/6是DNA损伤反应途径的关键组成部分，通过 调节TrP53乙酰化。在目标3中，我将对以下方面的互动进行详细评估 SMC5/6和BAT3-EP300，以及EID3对BAT3-EP300拮抗作用的生化分析。 EP300介导的TrP53乙酰化。我在获得K99/R00奖时假设SMC5/6充当 协调DNA修复和TrP53介导的DNA损伤的修复/监视复合体 回应。这一功能确保了减数分裂前期到中期I转换的保真度。

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.