title: Calcium-modulated rod outer segment membrane guanylate cyclase type 1 transduction machinery in the testes.
abstract: The importance of the second messengers, Ca(2+) and cyclic GMP, for the process of fertilization is well established; the mechanisms for their intracellular regulations in the testes are, however, poorly understood. This study documents the biochemical, molecular, and functional identity of a Ca(2+)-modulated membrane guanylate cyclase transduction machinery in bovine testes. The machinery is both inhibited and stimulated by free Ca(2+) levels. The Ca(2+)-sensor component of the inhibitory mode of the machinery is GCAP1 (guanylate cyclase activating protein type 1) and for the stimulatory mode is S100B. The transduction component is a Ca(2+)-driven rod outer segment membrane guanylate cyclase type 1, ROS-GC1. The cyclase is predominantly expressed in spermatogenic cells. GCAP1 expression is restricted to a small population of spermatogonia, whereas S100B is present in the majority of spermatocytes and spermatids. The expression of GCAP1 and S100B in spermatocytes and spermatids is mutually exclusive.
authors.affiliation: Department of Cell Biology, University of Medical Sciences, Poznan, Poland. ajanko@amp.edu.pl
authors.forename: Anna
authors.initials: A
authors.lastname: Jankowska
authors.forename: Beata
authors.initials: B
authors.lastname: Burczynska
authors.forename: Teresa
authors.initials: T
authors.lastname: Duda
authors.forename: Jerzy B
authors.initials: JB
authors.lastname: Warchol
authors.forename: Rameshwar K
authors.initials: RK
authors.lastname: Sharma
mesh_terms: D000818:Animals; D019556:COS Cells; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling; D002417:Cattle; D002462:Cell Membrane / Q000201:enzymology*; D002522:Chlorocebus aethiops; D006152:Cyclic GMP / Q000378:metabolism; D006162:Guanylate Cyclase / Q000378:metabolism*; D051604:Guanylate Cyclase-Activating Proteins / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D009414:Nerve Growth Factors / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000378:metabolism; D015290:Second Messenger Systems; D013091:Spermatogenesis; D013094:Spermatozoa / Q000166:cytology / Q000378:metabolism; D013737:Testis / Q000166:cytology / Q000378:metabolism*
chemical_list: D051604:Guanylate Cyclase-Activating Proteins; D008565:Membrane Proteins; D009414:Nerve Growth Factors; D011956:Receptors, Cell Surface; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C110715:guanylate cyclase 1; D006162:Guanylate Cyclase; D006152:Cyclic GMP; D002118:Calcium