title: The OsGEN-L protein from Oryza sativa possesses Holliday junction resolvase activity as well as 5'-flap endonuclease activity.
abstract: OsGEN-L has a 5'-flap endonuclease activity and plays an essential role in rice microspore development. The Class 4 RAD2/XPG family nucleases, including OsGEN-L, were recently found to have resolving activity for the Holliday junction (HJ), the intermediate of DNA strand recombination. In this study, we performed a detailed characterization of OsGEN-L, as a structure-specific endonuclease. Highly purified OsGEN-L was prepared as the full-length protein for in vitro endonuclease assays using various structured DNAs, and the 5'-flap endonuclease activity, which is stimulated in a PCNA-dependent manner, was demonstrated. In addition, the in vitro HJ resolving activity of OsGEN-L represents the first such activity originating from plant cells. OsGEN-L cleaved HJ at symmetrically related sites of the branch point. However, the two branched strands seemed to be cleaved individually, and not cooperatively, by each OsGEN-L monomer protein. The substrate specificity suggests that OsGEN-L functions in multiple processes of DNA metabolism in rice cells.
authors.affiliation: 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.forename: Yantao
authors.initials: Y
authors.lastname: Yang
authors.forename: Sonoko
authors.initials: S
authors.lastname: Ishino
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yamagami
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Kumamaru
authors.forename: Hikaru
authors.initials: H
authors.lastname: Satoh
authors.forename: Yoshizumi
authors.initials: Y
authors.lastname: Ishino
mesh_terms: D004260:DNA Repair / Q000235:genetics / Q000502:physiology; D045566:DNA, Cruciform / Q000378:metabolism*; D045585:Flap Endonucleases / Q000235:genetics / Q000378:metabolism*; D045565:Holliday Junction Resolvases / Q000235:genetics / Q000378:metabolism*; D012275:Oryza / Q000201:enzymology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism
chemical_list: D045566:DNA, Cruciform; D010940:Plant Proteins; D018809:Proliferating Cell Nuclear Antigen; D045585:Flap Endonucleases; D045565:Holliday Junction Resolvases