| Literature DB >> 28495749 |
Yusuke Kobayashi1, Osami Misumi2, Masaki Odahara3, Kota Ishibashi1, Masafumi Hirono4, Kumi Hidaka5, Masayuki Endo6, Hiroshi Sugiyama5,6, Hiroshi Iwasaki7, Tsuneyoshi Kuroiwa8, Toshiharu Shikanai1, Yoshiki Nishimura9.
Abstract
Holliday junctions, four-stranded DNA structures formed during homologous recombination, are disentangled by resolvases that have been found in prokaryotes and eukaryotes but not in plant organelles. Here, we identify monokaryotic chloroplast 1 (MOC1) as a Holliday junction resolvase in chloroplasts by analyzing a green alga Chlamydomonas reinhardtii mutant defective in chloroplast nucleoid (DNA-protein complex) segregation. MOC1 is structurally similar to a bacterial Holliday junction resolvase, resistance to ultraviolet (Ruv) C, and genetically conserved among green plants. Reduced or no expression of MOC1 in Arabidopsis thaliana leads to growth defects and aberrant chloroplast nucleoid segregation. In vitro biochemical analysis and high-speed atomic force microscopic analysis revealed that A. thaliana MOC 1 (AtMOC1) binds and cleaves the core of Holliday junctions symmetrically. MOC1 may mediate chloroplast nucleoid segregation in green plants by resolving Holliday junctions.Entities:
Mesh：
Substances：
Year: 2017 PMID： 28495749 DOI： 10.1126/science.aan0038
Source DB: PubMed Journal: Science ISSN： 0036-8075 Impact factor: 47.728