GLD-1, a cytoplasmic protein essential for oocyte differentiation, shows stage- and sex-specific expression during Caenorhabditis elegans germline development.
GLD-1, a putative RNA binding protein, is essential for oocyte development in Caenorhabditis elegans. A gld-1 null mutation abolishes hermaphrodite oogenesis and confers a tumorous germline phenotype in which presumptive female germ cells exit the meiotic pathway and return to the mitotic cell cycle. Here we demonstrate that gld-1(null) germ lines express female-specific, but not male-specific, molecular markers, indicating that gld-1 acts downstream of sexual fate specification to regulate oocyte differentiation. Immunolocalization studies identify GLD-1 as a cytoplasmic germline protein that displays differential accumulation during germline development. First, germ cells that are in the mitotic cell cycle contain low levels of GLD-1 that likely reflect a nonessential gld-1 function (negative regulation of proliferation in the mitotic germ line) revealed in previous genetic studies. Second, entry of presumptive oocytes into the meiotic pathway is accompanied by a strong increase in GLD-1 expression/accumulation. GLD-1 levels are high through the pachytene stage but fall to background as germ cells exit pachytene and complete oogenesis. The meiotic prophase accumulation pattern is consistent with GLD-1's essential role in oocyte differentiation, which may be to repress the translation of a subset of maternal RNAs synthesized during early oogenesis until late oogenesis when GLD-1 is absent.
Jones
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AR
Department of Genetics, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Francis
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R
Schedl
T
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D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins; D002453:Cell Cycle; D002454:Cell Differentiation; D012734:Disorders of Sex Development; D004625:Embryo, Nonmammalian / Q000502:physiology; D005260:Female; D005306:Fertilization; D019084:Fluorescent Antibody Technique, Indirect; D018507:Gene Expression Regulation, Developmental; D016147:Genes, Tumor Suppressor; D015801:Helminth Proteins / Q000032:analysis / Q000096:biosynthesis*; D066298:In Vitro Techniques; D008297:Male; D008540:Meiosis; D008938:Mitosis; D009865:Oocytes / Q000166:cytology* / Q000502:physiology*; D009866:Oogenesis; D012333:RNA, Messenger / Q000096:biosynthesis; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D012727:Sex Characteristics; D013091:Spermatogenesis; D014158:Transcription, Genetic
D029742:Caenorhabditis elegans Proteins; C094448:GLD-1 protein, C elegans; D015801:Helminth Proteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins