Open AccessDephosphorylation of a major sperm membrane protein is induced by egg jelly during sea urchin fertilization
Author(s) -
Gary E. Ward,
Victor D. Vacquier
Publication year - 1983
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.80.18.5578
Subject(s) - sperm , sea urchin , dephosphorylation , human fertilization , biology , vitelline membrane , flagellum , phosphorylation , biochemistry , polyacrylamide gel electrophoresis , microbiology and biotechnology , phosphatase , botany , anatomy , oocyte , enzyme , embryo , gene
A 160-kilodalton (kDa) protein ofArbacia punctulata sperm is constitutively phosphorylated on serine residues, as shown byin vivo 32 PO4 3- labeling. Exposure of sperm to solubilized egg jelly results in the immediate dephosphorylation (within 5 sec) of this protein and a simultaneous increase in its electrophoretic mobility (to an apparent molecular mass of 150 kDa). In its dephosphorylated form (150 kDa), the protein is a major component of the flagellar plasma membrane. In fact, silver-stained polyacrylamide gels show the 160/150-kDa protein to be the third most abundant protein in the whole flagellum. The spermatozoan must pass through the egg jelly layer on its way to the egg surface. The jelly-induced dephosphorylation of such an abundant sperm membrane protein may be an important event in the successful interaction of sperm and egg during fertilization.