title: Structure of the EndoMS-DNA Complex as Mismatch Restriction Endonuclease.
abstract: Archaeal NucS nuclease was thought to degrade the single-stranded region of branched DNA, which contains flapped and splayed DNA. However, recent findings indicated that EndoMS, the orthologous enzyme of NucS, specifically cleaves double-stranded DNA (dsDNA) containing mismatched bases. In this study, we determined the structure of the EndoMS-DNA complex. The complex structure of the EndoMS dimer with dsDNA unexpectedly revealed that the mismatched bases were flipped out into binding sites, and the overall architecture most resembled that of restriction enzymes. The structure of the apo form was similar to the reported structure of Pyrococcus abyssi NucS, indicating that movement of the C-terminal domain from the resting state was required for activity. In addition, a model of the EndoMS-PCNA-DNA complex was preliminarily verified with electron microscopy. The structures strongly support the idea that EndoMS acts in a mismatch repair pathway.
authors: Department of Bioscience, Nagahama Institute of Bio-Science and Technology, Tamura 1266, Nagahama, Shiga 526-0829, Japan.
authors: Setsu
authors: S
authors: Nakae
authors: Department of Bioscience, Nagahama Institute of Bio-Science and Technology, Tamura 1266, Nagahama, Shiga 526-0829, Japan.
authors: Atsushi
authors: A
authors: Hijikata
authors: Department of Bioscience, Nagahama Institute of Bio-Science and Technology, Tamura 1266, Nagahama, Shiga 526-0829, Japan.
authors: Toshiyuki
authors: T
authors: Tsuji
authors: Department of Bioscience, Nagahama Institute of Bio-Science and Technology, Tamura 1266, Nagahama, Shiga 526-0829, Japan.
authors: Kouki
authors: K
authors: Yonezawa
authors: Department of Bioscience, Nagahama Institute of Bio-Science and Technology, Tamura 1266, Nagahama, Shiga 526-0829, Japan.
authors: Ken-Ichi
authors: KI
authors: Kouyama
authors: Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka-shi, Fukuoka 812-8582, Japan.
authors: Kouta
authors: K
authors: Mayanagi
authors: Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, Fukuoka 812-8581, Japan.
authors: Sonoko
authors: S
authors: Ishino
authors: Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, Fukuoka 812-8581, Japan.
authors: Yoshizumi
authors: Y
authors: Ishino
authors: Department of Bioscience, Nagahama Institute of Bio-Science and Technology, Tamura 1266, Nagahama, Shiga 526-0829, Japan. Electronic address: t_shirai@nagahama-i-bio.ac.jp.
authors: Tsuyoshi
authors: T
authors: Shirai
mesh_terms: D019843:Archaeal Proteins / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D053843:DNA Mismatch Repair; D019641:DNA, Archaeal / Q000737:chemistry / Q000378:metabolism; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000378:metabolism*; D004706:Endodeoxyribonucleases / Q000737:chemistry* / Q000378:metabolism*; D008854:Microscopy, Electron; D008958:Models, Molecular; D011485:Protein Binding; D011487:Protein Conformation; D043903:Pyrococcus abyssi / Q000737:chemistry / Q000201:enzymology*
chemical_list: D019843:Archaeal Proteins; D019641:DNA, Archaeal; D004277:DNA, Single-Stranded; D004706:Endodeoxyribonucleases
keywords: DNA metabolism; DNA repair; protein modeling; protein-protein interaction; structural bioinformatics