The distinct and developmentally regulated patterns of expression of members of the mouse Cdc25 gene family suggest differential functions during gametogenesis.
Cdc25 genes encode protein threonine/tyrosine phosphatases that activate cyclin-dependent kinases. A cDNA encoding the murine homologue of the human Cdc25C gene was isolated in studies designed to identify those genes involved in regulating the mitotic and meiotic cell cycles of developing mouse germ cells. Northern blot and in situ hybridization along with immunoblot analyses were performed to determine the patterns of expression of Cdc25C compared to those of a second Cdc25 family member, Cdc25B. Murine Cdc25C transcripts of 2.1 kb were detected in midgestation embryos and in several adult tissues, including testis and ovary. The highest levels of Cdc25C transcripts were detected in the testis, with low levels of the 2.1-kb transcript and abundant levels of a 1.9-kb transcript that was not detected in the other tissues examined. In the testis, Cdc25C expression was localized in germ cells, specifically in late pachytene-diplotene spermatocytes and round spermatids, whereas Cdc25B expression was most readily detected in the somatic cells. In the ovary, Cdc25C expression was apparent in cumulus granulosa cells, whereas the expression of Cdc25B was detected in both growing oocytes and somatic cells, including the granulosa cells. These results not only indicate that the expression of the murine Cdc25 genes is lineage- and developmental stage-specific in the mouse testis and ovary but also suggest that the Cdc25 genes may have different functions in the germinal and somatic compartments of the ovary and the testis, only some of which are involved in cellular proliferation.
Wu
S
S
Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA.
Wolgemuth
D J
DJ
D000818:Animals; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D018076:DNA, Complementary / Q000235:genetics; D004790:Enzyme Induction; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006107:Granulosa Cells / Q000378:metabolism; D006801:Humans; D017403:In Situ Hybridization; D008297:Male; D008540:Meiosis; D051379:Mice / Q000235:genetics*; D008817:Mice, Mutant Strains; D008969:Molecular Sequence Data; D009866:Oogenesis / Q000502:physiology*; D010749:Phosphoprotein Phosphatases / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D013091:Spermatogenesis / Q000502:physiology*; D013737:Testis / Q000378:metabolism; D020687:cdc25 Phosphatases
D018797:Cell Cycle Proteins; D018076:DNA, Complementary; D011993:Recombinant Fusion Proteins; D010749:Phosphoprotein Phosphatases; C517009:CDC25C protein, human; C517010:Cdc25c protein, mouse; D020687:cdc25 Phosphatases