title: Differential time course of FSH/FSH receptor complex endocytosis within sertoli and germ cells during rat testis development.
abstract: Follicle-stimulating hormone (FSH) is required for initiation and maintenance of spermatogenesis, a dynamic process of cell proliferation and maturation. By using FSH-gold particles and pulse-chase experiments, we analyzed the kinetics of FSH endocytosis in Sertoli and germ cells during development. Ultrastructural time-dependent analysis demonstrates that FSH was first located on plasma membrane, before being accumulated within the endosomal compartment, in the early endosomes, identified by morphological criteria and Rab-5 colocalization. Thereafter, FSH-gold was routed to the degradation pathway. The FSH endocytosis kinetic was similar in Sertoli cells, spermatogonia and spermatocytes. However, quantitative analysis of gold particles revealed differences in the dynamic of FSH accumulation in the endosomes between immature and mature rats. This age-dependent kinetic of FSH endocytosis, mostly detectable by ultrastructural analysis associated with quantitative data, argues for a potential new regulatory mechanism of the FSH signalling pathway that could occur during maturation of testicular cells.
authors.affiliation: INSERM U 895, Université Paris Descartes, Paris, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Segretain
authors.forename: Jérome
authors.initials: J
authors.lastname: Gilleron
authors.forename: Diane
authors.initials: D
authors.lastname: Carette
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Denizot
authors.forename: Georges
authors.initials: G
authors.lastname: Pointis
mesh_terms: D000818:Animals; D004705:Endocytosis / Q000502:physiology*; D005640:Follicle Stimulating Hormone / Q000378:metabolism*; D005854:Germ Cells / Q000378:metabolism; D007700:Kinetics; D008297:Male; D046912:Multiprotein Complexes / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011962:Receptors, FSH / Q000378:metabolism*; D012708:Sertoli Cells / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D013091:Spermatogenesis / Q000502:physiology; D013094:Spermatozoa / Q000378:metabolism / Q000502:physiology; D013737:Testis / Q000254:growth & development* / Q000378:metabolism / Q000648:ultrastructure; D013997:Time Factors
chemical_list: D046912:Multiprotein Complexes; D011962:Receptors, FSH; D005640:Follicle Stimulating Hormone