PRESENCE OF A TRYPSIN-LIKE PROTEASE IN STARFISH SPERM ACROSOME

• Type: Article in International Scientific Journal
• Date: 1992

Authors

sousa, m (Author) ICBAS; Pedro Moradas Ferreira (Author) ICBAS; AZEVEDO, C (Author) Other

Journal

Title: Journal of Experimental Zoology

Vol. 261

Pages: 349-354

ISSN: 0022-104X

Publisher: John Wiley & Sons

Indexing

ISI Web of Knowledge - 13 Citations

Scopus - 6 Citations

Other information

Authenticus ID: 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.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6