Department of Biology, Carleton University, Ottawa, Ontario, Canada; Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada.
Department of Biochemistry, Research and Innovation Centre, University of Regina, Regina, Saskatchewan, Canada.
Biochem Biophys Res Commun. 2020 Dec 17;533(4):899-904. doi: 10.1016/j.bbrc.2020.09.083. Epub 2020 Sep 30.
Non-homologous end joining (NHEJ) is a highly conserved mechanism of DNA double-stranded break (DSB) repair. Here we utilize a computational protein-protein interaction method to identify human PRKACB as a potential candidate interacting with NHEJ proteins. We show that the deletion of its yeast homolog, TPK1 that codes for the protein kinase A catalytic subunit reduces the efficiency of NHEJ repair of breaks with overhangs and blunt ends in plasmid-based repair assays. Additionally, tpk1Δ mutants showed defects in the repair of chromosomal breaks induced by HO-site specific endonuclease. Our double deletion mutant analyses suggest that TPK1 and YKU80, a key player in NHEJ could function in parallel pathways. Altogether, here we report a novel involvement for TPK1 in NHEJ.
非同源末端连接（NHEJ）是一种高度保守的 DNA 双链断裂（DSB）修复机制。在这里，我们利用计算蛋白质-蛋白质相互作用的方法，鉴定出人源蛋白激酶 A 催化亚基 PRKACB 可能与 NHEJ 蛋白相互作用。我们发现，其酵母同源物 TPK1（编码蛋白激酶 A 催化亚基）的缺失降低了基于质粒的修复实验中带有突出端和齐平末端的断裂的 NHEJ 修复效率。此外，tpk1Δ 突变体在 HO 位点特异性内切酶诱导的染色体断裂修复中表现出缺陷。我们的双缺失突变体分析表明，TPK1 和 YKU80（NHEJ 的关键参与者）可能在平行途径中发挥作用。总的来说，我们在这里报告了 TPK1 在 NHEJ 中的一个新的作用。
