PRESENCE OF A TRYPSIN-LIKE PROTEASE IN STARFISH SPERM ACROSOME

• Tipo: Artigo em Revista Científica Internacional
• Data: 1992

Autores

sousa, m (Autor) ICBAS; Pedro Moradas Ferreira (Autor) ICBAS; AZEVEDO, C (Autor) Outra

Revista

Título: Journal of Experimental Zoology

Vol. 261

Páginas: 349-354

ISSN: 0022-104X

Editora: John Wiley & Sons

Indexação

ISI Web of Knowledge - 13 Citações

Scopus - 6 Citações

Outras Informações

ID Authenticus: P-001-PSV

DOI: 10.1002/jez.1402610314

Abstract (EN): Marthasterias glacialis sperm cells were treated with ionophore A23187, centrifuged, and the supernatants were assayed for esterase activity. With N-benzoyl-L-arginine ethyl ester-HCl (BAEE) as substrate, a net activity was determined which was not detectable when N-acetyl-L-tyrosine ethyl ester (ATEE) was used. The BAEE trypsin-like activity was inhibited by soybean trypsin inhibitor (SBTI), N-alpha-p-tosyl-L-lysine chloromethyl ketone-HCl (TLCK), and phenyl methyl sulfonyl fluoride (PMSF), but not by L-1-tosylamido-2-phenylethyl chloromethyl ketone (TPCK). The presence of proteolytic activity in acrosomal exudates was further demonstrated by gelatin-sodium dodecyl sulfate-polyacrylamide gel electrophoretic zymography (gelatin-SDS-PAGE). The presence of several bands of low proteolytic activity and of one band of high proteolytic activity, which also has the lower molecular weight, together with the fact that all are inhibited by benzamidine, suggests the existence of a trypsin-like proteinase system. The effect of the acrosomal exudate on the oocyte jelly coat was investigated by SDS-PAGE analysis. All jelly proteins appeared to be digested by the acrosomal enzymes. Furthermore, if SBTI is added shortly after insemination, the sperm fail to fertilize the oocytes. These results indicate that the starfish sperm acrosomal vesicle contains a trypsin-like protease which may be involved in sperm penetration through the oocyte jelly coat.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 6