title: MEX-3 is a KH domain protein that regulates blastomere identity in early C. elegans embryos.
abstract: After the first division of the C. elegans embryo, the posterior blastomere can produce numerous muscles while the anterior blastomere cannot. We show here that maternal-effect lethal mutations in the gene mex-3 cause descendants of the anterior blastomere to produce muscles by a pattern of development similar to that of a descendant of the wild-type posterior blastomere. mex-3 encodes a probable RNA-binding protein that is distributed unequally in early embryos and that is a component of germline-specific granules called P granules. We propose that MEX-3 contributes to anterior-posterior asymmetry by regulating one or more mRNAs involved in specifying the fate of the posterior blastomere.
authors.affiliation: Department of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA.
authors.forename: B W
authors.initials: BW
authors.lastname: Draper
authors.forename: C C
authors.initials: CC
authors.lastname: Mello
authors.forename: B
authors.initials: B
authors.lastname: Bowerman
authors.forename: J
authors.initials: J
authors.lastname: Hardin
authors.forename: J R
authors.initials: JR
authors.lastname: Priess
mesh_terms: D000483:Alleles; D000818:Animals; D001483:Base Sequence; D001757:Blastomeres / Q000166:cytology*; D017173:Caenorhabditis elegans / Q000196:embryology*; D029742:Caenorhabditis elegans Proteins; D003593:Cytoplasm / Q000378:metabolism; D003594:Cytoplasmic Granules / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D017238:Genes, Helminth; D005804:Genes, Lethal; D015801:Helminth Proteins / Q000502:physiology*; D006801:Humans; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009024:Morphogenesis; D009132:Muscles / Q000196:embryology; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D029742:Caenorhabditis elegans Proteins; D015801:Helminth Proteins; C102175:MEX-3 protein, C elegans; D012333:RNA, Messenger; D016601:RNA-Binding Proteins