title: GLD-3, a bicaudal-C homolog that inhibits FBF to control germline sex determination in C. elegans.
abstract: The FBF RNA binding proteins control multiple aspects of C. elegans germline development, including sex determination. FBF promotes the oocyte fate at the expense of spermatogenesis by binding a regulatory element in the fem-3 3'UTR and repressing this sex-determining gene. Here we report the discovery of GLD-3, a Bicaudal-C homolog and cytoplasmic protein that physically interacts with FBF. Using RNAi and a gld-3 deletion mutant, we show that GLD-3 promotes the sperm fate, a sex determination effect opposite to that of FBF. By epistasis analysis, GLD-3 acts upstream of FBF, and, in a yeast three-hybrid assay, GLD-3 interferes specifically with FBF binding to the fem-3 3'UTR. We propose that GLD-3 binds FBF and thereby inhibits its repression of target mRNAs.
authors.affiliation: Howard Hughes Medical Institute, 433 Babcock Drive, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Christian R
authors.initials: CR
authors.lastname: Eckmann
authors.forename: Brian
authors.initials: B
authors.lastname: Kraemer
authors.forename: Marvin
authors.initials: M
authors.lastname: Wickens
authors.forename: Judith
authors.initials: J
authors.lastname: Kimble
mesh_terms: D020413:3' Untranslated Regions; D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology / Q000235:genetics / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D029721:Drosophila Proteins; D005260:Female; D008297:Male; D008969:Molecular Sequence Data; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D019849:Sex Determination Processes; D013091:Spermatogenesis / Q000502:physiology; D013094:Spermatozoa / Q000502:physiology*
chemical_list: D020413:3' Untranslated Regions; C113767:BicC protein, Drosophila; D029742:Caenorhabditis elegans Proteins; D029721:Drosophila Proteins; C469731:GLD-3 protein, C elegans; D016601:RNA-Binding Proteins; C075059:fem-3 protein, C elegans; C109286:fem-3-binding protein, C elegans