Research team of Lin Zhonghui from Fuzhou University has made important progress in the study of molecular mechanism of DNA damage repair

Organisms, including human beings, are exposed to UV radiation, free radicals and other chemical substances every day, which cause DNA damage in vivo Even if they are not affected by the external environment, DNA replication will also produce errors when the cell itself divides Even so, why can most organisms maintain the stability of their genome and survive normally? Research has found that the body has a security system that can monitor and repair DNA at all times The Nobel Prize in chemistry in 2015 was awarded to three scientists who studied the mechanism of DNA repair at the molecular level Recently, the research team of Lin Zhonghui, School of chemistry, Fuzhou University, has made important progress in the study of the molecular mechanism of DNA damage repair The research results were published in nature Chemical Biology (DOI: 10.1038 / s41589-019-0377-4) with the title of "structural basis of sequence specific Holliday junction clarity by moc1" Holliday junction (HJ) was first discovered by British molecular biologist Robin Holliday in 1964 It is a kind of cross shaped DNA junction formed in the process of DNA homologous recombination damage repair It exists in phages, bacteria, fungi, plants and even animal cells After DNA damage repair, HJ must be dissociated under the action of HJ dissociation enzyme, so as to make two homologous DNA double strands separate and become linear DNA 1 again Moc1 is a chloroplast specific HJ dissociatase 2 Lin Zhonghui's research team combined structural biology, computational biology and a large number of biochemical data to not only reveal the catalytic mechanism of HJ dissociation enzyme moc1 at the atomic level, but also provide an important indication for the pending substrate specific recognition mechanism of ruvc family What's more, aiming at the scientific problem of how nuclease can transform the small difference in DNA sequence into the huge difference in its catalytic activity, this study innovatively proposes a bimetallic ion assisted DNA sequence specific selectivity mechanism Lin Zhonghui, researcher of Fuzhou University, Professor Huang Mingdong and Professor Li Jinyu are the co correspondents of the paper, Lin Huajian, doctoral student, Zhang Danping, research assistant and Zuo Ke are the co first authors, among which Lin Huajian is under the guidance of Professor Lin Zhonghui and Professor Huang Mingdong Professor Li Jinyu's research group completed the molecular dynamics simulation work Associate Professor Yuan Cai participated in the modification of crystal structure This research has been supported by the national youth talent plan, the National Natural Science Foundation, the Fujian high level talent introduction plan and the special funds for leading talents in Colleges and universities of Fujian Province Shanghai synchrotron radiation source (SSRF) bl17u1 / bl18u1 / bl19u1 provides important technical support for this study.