title: Acrosin inhibitor detection along the boar epididymis.
abstract: Epididymal sperm maturation represents a key step in the reproduction process. Spermatozoa are exposed to epididymal fluid components representing the natural environment essential for their post-testicular maturation. Changes in sperm membrane proteins are influenced by proteolytic, glycosylation and deglycosylation enzymes present in the epididymal fluid. Accordingly, the occurrence of inhibitors of these enzymes in the epididymis is very important for the regulation of sperm membrane protein processing. In the present study, we monitored acrosin inhibitor distribution in boar epididymal fluid and in spermatozoa from different segments of the organ. Using specific polyclonal antibody we registered increasing signal of the acrosin inhibitor (AI) from caput to cauda epididymis. Mass spectroscopy examination of the immunoprecipitated acrosin inhibitor (12 kDa) unequivocally identified sperm-associated acrosin inhibitor (SAAI) in the epididymal tissue. Lectin staining showed N-glycosylation in AI from boar epididymis. Protein detection of AI was supported by the results of semi-quantitative RT-PCR showing the presence of mRNA specifically coding for SAAI and similarly increasing throughout the epididymal duct, from its proximal to distal part. Additionally, the immunofluorescence technique showed the AI localization in the secretory tissue of caput, corpus and cauda epididymis, and in the acrosome region and midpiece of the sperm.
authors.affiliation: Laboratory of Reproductive Biology, Institute of Biotechnology, Academy of Sciences of the Czech Republic, v.v.i., Prague, Czech Republic. Electronic address: pavlam@ibt.cas.cz.
authors.forename: Pavla
authors.initials: P
authors.lastname: Maňásková-Postlerová
authors.affiliation: Laboratory of Reproductive Biology, Institute of Biotechnology, Academy of Sciences of the Czech Republic, v.v.i., Prague, Czech Republic; Department of Biochemistry, Faculty of Science, Charles University, Prague, Czech Republic.
authors.forename: Nina
authors.initials: N
authors.lastname: Cozlová
authors.affiliation: Laboratory of Reproductive Biology, Institute of Biotechnology, Academy of Sciences of the Czech Republic, v.v.i., Prague, Czech Republic.
authors.forename: Andriy
authors.initials: A
authors.lastname: Dorosh
authors.affiliation: Department of Biochemistry, Faculty of Science, Charles University, Prague, Czech Republic; Institute of Microbiology, Academy of Sciences of the Czech Republic, v.v.i., Prague, Czech Republic.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Šulc
authors.affiliation: INRA-CNRS-Universite de Tours-Haras Nationaux, Nouzilly, France; Pôle Génétique, IFIP Institut du Porc, Le Rheu, France.
authors.forename: Benoit
authors.initials: B
authors.lastname: Guyonnet
authors.affiliation: Laboratory of Reproductive Biology, Institute of Biotechnology, Academy of Sciences of the Czech Republic, v.v.i., Prague, Czech Republic.
authors.forename: Věra
authors.initials: V
authors.lastname: Jonáková
mesh_terms: D000176:Acrosin / Q000037:antagonists & inhibitors*; D000595:Amino Acid Sequence; D000818:Animals; D004791:Enzyme Inhibitors / Q000097:blood / Q000737:chemistry / Q000378:metabolism*; D004822:Epididymis / Q000378:metabolism*; D015870:Gene Expression; D006031:Glycosylation; D008297:Male; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D021381:Protein Transport; D059748:Proteolysis; D016415:Sequence Alignment; D013094:Spermatozoa / Q000378:metabolism; D013552:Swine
chemical_list: D004791:Enzyme Inhibitors; D000176:Acrosin
keywords: Acrosin inhibitor; Boar epididymis; Spermatozoa