Characterization of the mus-10 and recQ genes involving in DNA repair, recombination, and senescence

粗神经孢子虫有2个同源基因recQ1和recQ2，分别编码recQ解旋酶。我们破坏了这些基因并描述了表型。recQ1基因与mus19和qde-3基因相同。mus19突变体对MMS敏感。EMS， MNNG， 4NQO和喜树碱。上位分析表明，mus19属于重组修复和复制后修复。突变频率不高，重组频率不高。在mus19菌株中，我们无法识别出“quering”，即N. crassa的基因沉默。在该菌株中也未观察到菌丝老化。与mus19菌株一样，recQ2突变体对诱变剂敏感。我们正在研究该菌株的其他表型。mus-10突变体萌发后生长正常，但几天后生长缓慢，最终停止生长。该菌株对紫外、MMS敏感。上位性分析表明，与mus-18组合对诱变原的敏感性具有协同作用，而其他组合对诱变原的敏感性没有协同作用。端粒长度在衰老阶段没有变化。一些数据表明，该突变体在线粒体DNA稳定性方面存在缺陷。

Neurospora crassa has 2 recQ homolog genes, recQ1 and recQ2, which encode RecQ helicase. We disrupted those genes and characterized phenotypes. Gene recQ1 was same to mus-19 and also qde-3 genes. The mus-19 mutant is sensitive to MMS. EMS, MNNG, 4NQO and camptotecin. Epistasis analyzes showed that mus-19 belonged to recombination repair and postreplication repair. It did not show high mutation frequency and high recombination frequency. In the mus-19 strain we could not identify "quering" that is gene silencing in N. crassa. Also aging of the hyphae was not observed in this strain. Like the mus-19 strain, the recQ2 mutant was sensitive to mutagens. We are investigating other phenotype of this strain.The mus-10 mutant grow normally after germination, but several days later the growth became slow and finally stopped. This strain was sensitive UV and MMS. Epistasis analyzes showed that combination with mus-18 become synergistic in mutagen sensitivity, but other combination did not. Telomere length did not change at the aging step. Some data showed this mutant had defect in mitochondria DNA stability.