GLD-3, a bicaudal-C homolog that inhibits FBF to control germline sex determination in C. elegans.
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.
Eckmann
Christian R
CR
Howard Hughes Medical Institute, 433 Babcock Drive, University of Wisconsin-Madison, Madison, WI 53706, USA.
Kraemer
Brian
B
Wickens
Marvin
M
Kimble
Judith
J
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*
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