title: Crystal structure of Ski8p, a WD-repeat protein with dual roles in mRNA metabolism and meiotic recombination.
abstract: Ski8p is a WD-repeat protein with an essential role for the Ski complex assembly in an exosome-dependent 3'-to-5' mRNA decay. In addition, Ski8p is involved in meiotic recombination by interacting with Spo11p protein. We have determined the crystal structure of Ski8p from Saccharomyces cerevisiae at 2.2 A resolution. The structure reveals that Ski8p folds into a seven-bladed beta propeller. Mapping sequence conservation and hydrophobicities of amino acids on the molecular surface of Ski8p reveals a prominent site on the top surface of the beta propeller, which is most likely involved in mediating interactions of Ski8p with Ski3p and Spo11p. Mutagenesis combined with yeast two-hybrid and GST pull-down assays identified the top surface of the beta propeller as being required for Ski8p binding to Ski3p and Spo11p. The functional implications for Ski8p function in both mRNA decay and meiotic recombination are discussed.
authors.affiliation: Laboratory of Macromolecular Structure, Institute of Molecular and Cell Biology, 30 Medical Drive, Singapore 117609.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Cheng
authors.forename: Yuying
authors.initials: Y
authors.lastname: Liu
authors.forename: Chernhoe
authors.initials: C
authors.lastname: Wang
authors.forename: Roy
authors.initials: R
authors.lastname: Parker
authors.forename: Haiwei
authors.initials: H
authors.lastname: Song
mesh_terms: D000595:Amino Acid Sequence; D003461:Crystallography; D004706:Endodeoxyribonucleases; D004950:Esterases / Q000378:metabolism; D008540:Meiosis; D008969:Molecular Sequence Data; D016296:Mutagenesis / Q000235:genetics; D009154:Mutation / Q000235:genetics; D009687:Nuclear Proteins / Q000378:metabolism; D025941:Protein Interaction Mapping; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D011995:Recombination, Genetic; D020449:Repetitive Sequences, Amino Acid; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D040681:Structural Homology, Protein; D000099257:Meiotic Recombination Protein SPO11
chemical_list: D004706:Endodeoxyribonucleases; D004950:Esterases; D009687:Nuclear Proteins; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; D000099257:Meiotic Recombination Protein SPO11; C406671:SKI3 protein, S cerevisiae; C079882:SKI8 protein, S cerevisiae