title: Genetic analyses using a mouse cell cycle mutant identifies magoh as a novel gene involved in Cdk regulation.
abstract: Many of the genes that control cyclin-dependent kinase (Cdks) activity have been identified by genetic research using yeast mutants. Suppression analysis and synthetic enhancement analysis are two broad approaches to the identification of genetic interaction networks in yeasts. Here we show, by genetic analyses using a mammalian cell cycle mutant, that mouse magoh is involved in Cdk regulation. Magoh, a homolog of the Drosophila mago nashi gene product, is a component of the splicing-dependent exon-exon junction complex (EJC). We show that, in addition to ccnb1 and cks2, magoh is also a dosage suppressor of the mouse temperature-sensitive cdc2 mutant, and synthetic enhancement of the cdc2 ts phenotype by RNA interference (RNAi) of magoh is observed in a manner similar to RNAi of cks2. Moreover, the depletion of magoh by RNAi causes cold-sensitive defects in the cell cycle transition, and exogenous cks2 expression partially suppresses the defect. Consistent with the genetic evidence, magoh RNAi caused defects in the expression of Cdc2 or Cks proteins, and introns of cks genes strongly affected protein expression levels. Thus, these data suggest that mouse Magoh is related to cell cycle regulation.
authors.affiliation: Genome and Drug Research Center, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Inaki
authors.forename: Dai
authors.initials: D
authors.lastname: Kato
authors.forename: Takahiko
authors.initials: T
authors.lastname: Utsugi
authors.forename: Fumitoshi
authors.initials: F
authors.lastname: Onoda
authors.forename: Fumio
authors.initials: F
authors.lastname: Hanaoka
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Murakami
mesh_terms: D000818:Animals; D016203:CDC2 Protein Kinase / Q000235:genetics; D042846:CDC2-CDC28 Kinases / Q000235:genetics; D017489:CDC28 Protein Kinase, S cerevisiae / Q000235:genetics; D018929:Cell Culture Techniques; D002453:Cell Cycle / Q000235:genetics*; D018797:Cell Cycle Proteins; D018844:Cyclin-Dependent Kinases / Q000235:genetics*; D005434:Flow Cytometry; D015971:Gene Expression Regulation, Enzymologic; D005822:Genetic Vectors; D051379:Mice; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics; D014162:Transfection
chemical_list: D018797:Cell Cycle Proteins; C491493:Magoh protein, mouse; D009687:Nuclear Proteins; D034741:RNA, Small Interfering; D016203:CDC2 Protein Kinase; D042846:CDC2-CDC28 Kinases; D017489:CDC28 Protein Kinase, S cerevisiae; C474110:Cks1 protein, mouse; C474109:Cks2 protein, mouse; D018844:Cyclin-Dependent Kinases