Molecular mechanisms utilized by alternative c-kit gene products in the control of spermatogonial proliferation and sperm-mediated egg activation.
The c-kit proto-oncogene plays a dual role in the control of male fertility in mice through two alternative gene products: (1). c-kit [the transmembrane tyrosine kinase receptor for stem cell factor (SCF)], which is expressed and functional in differentiating spermatogonia of the postnatal testis, in which c-kit is essential for pre-meiotic proliferation; and (2). tr-kit, an intracellular protein which is specifically accumulated during spermiogenesis through the use of an alternative intronic promoter, and which is able to trigger mouse egg activation when microinjected into the cytoplasm of metaphase II arrested oocytes. Here, we summarize the most recent findings about the molecular pathways through which c-kit regulates cell cycle progression in mitotic germ cells, and those through which sperm-derived tr-kit triggers parthenogenetic completion of meiosis II and pronuclear formation in microinjected mouse eggs.
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Dipartimento di Sanita' Pubblica e Biologia Cellulare, Sezione di Anatomia, Universita' degli Studi di Roma Tor Vergata, Rome, Italy. pellegrino.rossi@med.uniroma2.it
Dolci
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Sette
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Geremia
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D017398:Alternative Splicing; D000818:Animals; D002453:Cell Cycle; D002455:Cell Division / Q000502:physiology*; D008297:Male; D008540:Meiosis; D051379:Mice; D015394:Molecular Structure; D009865:Oocytes / Q000166:cytology / Q000502:physiology; D019009:Proto-Oncogene Proteins c-kit / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*; D013084:Sperm-Ovum Interactions / Q000502:physiology*; D013091:Spermatogenesis; D013093:Spermatogonia / Q000166:cytology*; D013094:Spermatozoa / Q000502:physiology
D019009:Proto-Oncogene Proteins c-kit