Alligand Brendan, Le Breton Magali, Marquis Damien, Vallette François, Fleury Fabrice
Team 3 Mechanism and Regulation of DNA Repair, UFIP, CNRS UMR 6286, Nantes University, France; Team 9 Apoptosis in Nervous Central System Tumours, CRCINA, INSERM U892, Nantes University, France.
Team 3 Mechanism and Regulation of DNA Repair, UFIP, CNRS UMR 6286, Nantes University, France.
Biochimie. 2017 Aug;139:115-124. doi: 10.1016/j.biochi.2017.05.020. Epub 2017 May 29.
Homologous Recombination enables faithful repair of the deleterious double strand breaks of DNA. This pathway relies on Rad51 to catalyze homologous DNA strand exchange. Rad51 is known to be phosphorylated in a sequential manner on Y315 and then on Y54, but the effect of such phosphorylation on Rad51 function remains poorly understood. We have developed a phosphomimetic model in order to study all the phosphorylation states. With the purified phosphomimetic proteins we performed in vitro assays to determine the activity of Rad51. Here we demonstrate the inhibitory effect of the double phosphomimetic mutant and suggest that it may be due to a defect in nucleofilament formation.
同源重组能够准确修复DNA的有害双链断裂。该途径依赖于Rad51催化同源DNA链交换。已知Rad51在Y315位点先发生磷酸化，随后在Y54位点磷酸化，但这种磷酸化对Rad51功能的影响仍知之甚少。为了研究所有的磷酸化状态，我们构建了一个拟磷酸化模型。利用纯化的拟磷酸化蛋白，我们进行了体外实验以测定Rad51的活性。在此我们证明了双拟磷酸化突变体的抑制作用，并表明这可能是由于核丝形成缺陷所致。
