Bhandari Nirajan, Rourke Christine, Wilmoth Thomas, Bheemreddy Alekya, Schulman David, Collins Dina, Smith Harold E, Golden Andy, Jaramillo-Lambert Aimee
Department of Biological Sciences, University of Delaware, Newark, Delaware 19701.
National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892.
G3 (Bethesda). 2020 Apr 9;10(4):1183-1191. doi: 10.1534/g3.119.400927.
Topoisomerase II is an enzyme with important roles in chromosome biology. This enzyme relieves supercoiling and DNA and RNA entanglements generated during mitosis. Recent studies have demonstrated that Topoisomerase II is also involved in the segregation of homologous chromosomes during the first meiotic division. However, the function and regulation of Topoisomerase II in meiosis has not been fully elucidated. Here, we conducted a genetic suppressor screen in to identify putative genes that interact with during meiosis. Using a temperature-sensitive allele of , , we identified eleven suppressors of -induced embryonic lethality. We used whole-genome sequencing and a combination of RNAi and CRISPR/Cas9 genome editing to identify and validate the responsible suppressor mutations. We found both recessive and dominant suppressing mutations that include one intragenic and 10 extragenic loci. The extragenic suppressors consist of a known Topoisomerase II-interacting protein and two novel interactors. We anticipate that further analysis of these suppressing mutations will provide new insights into the function of Topoisomerase II during meiosis.
拓扑异构酶II是一种在染色体生物学中具有重要作用的酶。这种酶可缓解有丝分裂过程中产生的超螺旋以及DNA和RNA缠结。最近的研究表明，拓扑异构酶II也参与第一次减数分裂期间同源染色体的分离。然而，拓扑异构酶II在减数分裂中的功能和调控尚未完全阐明。在此，我们在[具体实验对象]中进行了遗传抑制子筛选，以鉴定在减数分裂期间与[相关基因]相互作用的假定基因。利用[相关基因]的温度敏感等位基因[具体名称]，我们鉴定出了11个抑制[相关基因]诱导的胚胎致死性的抑制子。我们使用全基因组测序以及RNA干扰和CRISPR/Cas9基因组编辑的组合来鉴定和验证相关的抑制子突变。我们发现了隐性和显性抑制突变，其中包括一个基因内位点和10个基因外位点。基因外抑制子由一种已知的与拓扑异构酶II相互作用的蛋白质和两个新的相互作用因子组成。我们预计对这些抑制突变的进一步分析将为拓扑异构酶II在减数分裂期间的功能提供新的见解。
