title: Implications of caveolae in testicular and epididymal myoid cells to sperm motility.
abstract: Seminiferous tubules of the testis and epididymal tubules in adult rodents are enveloped by contractile myoid cells, which move sperm and fluids along the male reproductive tract. Myoid cells in the testis influence Sertoli cells by paracrine signaling, but their role in the epididymis is unknown. Electron microscopy revealed that elongated myoid cells formed several concentric layers arranged in a loose configuration. The edges of some myoid cells in a given layer closely approximated one another, and extended small foot-like processes to cells of overlying layers. Gap junction proteins, connexins 32 and 43, were detected within the myoid cell layers by immunohistochemistry. These myoid cells also had caveolae that contained caveolin-1 and cavin-1 (also known as PTRF). The number of caveolae per unit area of plasma membrane was significantly reduced in caveolin-1-deficient mice (Cav1(-/-) ). Morphometric analyses of Cav1-null testes revealed an enlargement in whole-tubule and epithelial profile areas, whereas these parameters were slightly reduced in the epididymis. Although sperm are non-motile as they pass through the proximal epididymis, statistical analyses of cauda epididymidis sperm concentrations revealed no significant differences between wild-type and Cav1(-/-) mice. Motility analyses, however, indicated that sperm velocity parameters were reduced while beat cross frequency was higher in gametes of Cav1(-/-) mice. Thus while caveolae and their associated proteins are not necessary for myoid cell contractility, they appear to be crucial for signaling with the epididymal epithelium to regulate the proper acquisition of sperm motility. Mol. Reprod. Dev. 83: 526-540, 2016. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Anatomy and Cell Biology, McGill University, Montreal, Canada.
authors.forename: Regiana L
authors.initials: RL
authors.lastname: Oliveira
authors.affiliation: Department of Anatomy and Cell Biology, McGill University, Montreal, Canada.
authors.forename: Adam
authors.initials: A
authors.lastname: Parent
authors.affiliation: Department of Anatomy and Cell Biology, McGill University, Montreal, Canada.|INRS-Institut Armand Frappier, Université du Québec, Laval, Quebec, Canada.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Cyr
authors.affiliation: INRS-Institut Armand Frappier, Université du Québec, Laval, Quebec, Canada.
authors.forename: Mary
authors.initials: M
authors.lastname: Gregory
authors.affiliation: Department of Anatomy and Cell Biology, McGill University, Montreal, Canada.
authors.forename: Craig A
authors.initials: CA
authors.lastname: Mandato
authors.affiliation: Department of Anatomy and Cell Biology, McGill University, Montreal, Canada.
authors.forename: Charles E
authors.initials: CE
authors.lastname: Smith
authors.affiliation: Department of Anatomy and Cell Biology, McGill University, Montreal, Canada.
authors.forename: Louis
authors.initials: L
authors.lastname: Hermo
mesh_terms: D000818:Animals; D021941:Caveolae / Q000378:metabolism*; D051242:Caveolin 1 / Q000235:genetics / Q000378:metabolism; D018031:Connexin 43 / Q000235:genetics / Q000378:metabolism; D017630:Connexins / Q000235:genetics / Q000378:metabolism; D004822:Epididymis / Q000166:cytology / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D013081:Sperm Motility / Q000502:physiology*; D013737:Testis / Q000166:cytology / Q000378:metabolism*; D000097002:Gap Junction beta-1 Protein
chemical_list: D051242:Caveolin 1; D018031:Connexin 43; D017630:Connexins; D008565:Membrane Proteins; D016601:RNA-Binding Proteins; D000097002:Gap Junction beta-1 Protein; C112745:Cavin1 protein, mouse; C543076:GJA1 protein, mouse