DHH/DHHA1家族蛋白在耐辐射奇球菌DNA损伤响应和修复中的作用

耐辐射奇球菌(Deinococcus radiodurans，dr)对逆境的强大抗性得益于其高效的DNA损伤响应系统和DNA修复系统。其体内含有两个DHH/DHHA1家族成员，drRecJ和drRecJ-like蛋白。drRecJ被证实是耐辐射奇球菌DNA修复系统中的关键蛋白，其尚有一些分子机制还不明确。而drRecJ-like蛋白的功能和机制还未见报道，其同源蛋白在其他细菌中往往和基因组稳定性、环境抗逆等密切相关，因此可能也会对耐辐射奇球菌体内的DNA损伤响应和修复系统非常重要。本项目拟利用生物化学、结构生物学和遗传学等研究手段对耐辐射奇球菌中两个DHH/DHHA1家族蛋白做功能和机制上的深入研究，预期得到的结果将不仅有助于总结DHH/DHHA1家族成员普遍的功能和分子机制，而且可以帮我们了解更多耐辐射奇球菌的抗逆机理和相关蛋白协同进化历程，以便我们更好地利用这类生物资源。

The extreme radiation resistance of Deinococcus radiodurans has been attributed to a robust DNA damage response system and DNA repair system. D. radiodurans possesses two DHH/DHHA1 family members, RecJ and RecJ-like. drRecJ has been proved to be a key protein for DNA repair, with some molecular mechanism unsolved. While the function and mechanism of drRecJ-like are unknown. The homologs of drRecJ-like usually relate to genome maintenance and stress tolerance, which implies drRecJ-like also participates in DNA damage response and repair in D. radiodurans. This project intends to use biochemical, structural biology and genetic research methods to study the function and mechanism of two DHH/DHHA1 family proteins in D. radiodurans. The prospective results can not only provide the universal functions and molecular mechanisms of the DHH/DHHA1 family proteins, but also help us dig out the stress resistance and protein co-evolution mechanisms of D. radiodurans, and therefore make better use of this kind of biological resources.