Dephosphorylation of sperm guanylate cyclase during sea urchin fertilization

Thesis/Dissertation · Tue Jan 01 00:00:00 EST 1985

OSTI ID:6655811

Ward, G E

When intact Arbacia punctulata spermatozoa are exposed to solubilized egg jelly, the electrophoretic mobility of an abundant sperm flagellar membrane protein changes from an apparent molecular mass of 160 kDa to 150 kDa. A. punctulata spermatozoa can be labeled in vivo with /sup 32/P-labeled cells it was demonstrated that the mobility shift of the 160-kDa protein is due to dephosphorylation. The peptide resact (Cys-Val-Thr-Gly-Ala-Pro-Gly-Cys-Val-Gly-Gly-Gly-Arg-Leu-NH/sub 2/) is the component of egg jelly which is responsible for inducing the dephosphorylation. The 160/150-kdal sperm membrane protein has been purified to homogeneity by affinity chromatography on concanavalin A-agarose, and identified as sperm guanylate cyclase. The enzymatic activity of the guanylate cyclase is tightly coupled to its phosphorylation state. Resact has been shown to act as a potent chemoattractant for A. punctulata spermatozoa. The chemotactic response is concentration-dependent, is abolished by pretreatment of the spermatozoa with resact, and shows an absolute requirement for external calcium. This work represents the first demonstration of animal sperm chemotaxis in response to a precisely-defined molecule of egg origin. The results established a new, biologically meaningful function for resact, and may implicate sperm guanylate cyclase and cGMP in flagellar function and the chemotactic response.

• Research Organization: California Univ., San Diego (USA)
• OSTI ID: 6655811
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CELL MEMBRANES
CYCLASES
PROTEINS
SPERMATOZOA
PHOSPHORYLATION
AMP
ELECTROPHORESIS
EXTRACTION CHROMATOGRAPHY
FERTILIZATION
LABELLED COMPOUNDS
LABELLING
NUCLEOTIDES
PEPTIDES
PHOSPHORUS 32
TRACER TECHNIQUES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CELL CONSTITUENTS
CHEMICAL REACTIONS
CHROMATOGRAPHY
DAYS LIVING RADIOISOTOPES
ENZYMES
GAMETES
GERM CELLS
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
LYASES
MEMBRANES
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
PHOSPHORUS ISOTOPES
RADIOISOTOPES
SEPARATION PROCESSES
550201* - Biochemistry- Tracer Techniques