title: Cyclin D regulation of a sexually dimorphic asymmetric cell division.
abstract: The C. elegans somatic gonadal precursor cell (SGP) divides asymmetrically to establish gonad-specific coordinates in both sexes. In addition, the SGP division is sexually dimorphic and initiates sex-specific programs of gonadogenesis. Wnt/MAPK signaling determines the gonadal axes, and the FKH-6 transcription factor specifies the male mode of SGP division. In this paper, we demonstrate that C. elegans cyclin D controls POP-1/TCF asymmetry in the SGP daughters as well as fkh-6 and rnr expression in the SGPs. Although cyclin D mutants have delayed SGP divisions, the cyclin D defects are not mimicked by other methods of retarding the SGP division. We find that EFL-1/E2F has an antagonistic effect on fkh-6 expression and gonadogenesis, which is relieved by cyclin D activity. We propose that cyclin D and other canonical regulators of the G1/S transition coordinate key regulators of axis formation and sex determination with cell cycle progression to achieve the sexually dimorphic SGP asymmetric division.
authors.affiliation: Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA. cetilmann@loyola.edu
authors.forename: Christopher
authors.initials: C
authors.lastname: Tilmann
authors.forename: Judith
authors.initials: J
authors.lastname: Kimble
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000033:anatomy & histology* / Q000254:growth & development* / Q000502:physiology; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D002455:Cell Division / Q000502:physiology*; D056741:Cyclin D; D016213:Cyclins / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism; D006066:Gonads / Q000033:anatomy & histology / Q000254:growth & development; D006609:High Mobility Group Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D009024:Morphogenesis; D020125:Mutation, Missense; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D012727:Sex Characteristics; D015398:Signal Transduction / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D029742:Caenorhabditis elegans Proteins; D018797:Cell Cycle Proteins; D056741:Cyclin D; D016213:Cyclins; D004268:DNA-Binding Proteins; D051858:Forkhead Transcription Factors; D006609:High Mobility Group Proteins; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; C400701:cyd-1 protein, C elegans; C497669:fkh-6 protein, C elegans; C096787:pop-1 protein, C elegans