title: Phospholipase activity of sea urchin sperm: its possible involvement in membrane fusion.
abstract: Phospholipase activity of egg-water treated Arbacia punctulata and Lytechinus variegatus sperm was shown to result from the sequential action of phospholipase A and lysophospholipase. A transient burst of phospholipase A activity followed induction of the acrosome reaction with egg water. The time of appearance suggested an acrosomal localization of the enzyme. The peak activity of phospholipase A correlated with initiation of sperm-egg fusion, suggesting a role for sea urchin sperm phospholipase A in membrane fusion and/or egg activation during fertilization.
mesh_terms: D000177:Acrosome / Q000201:enzymology; D000818:Animals; D005260:Female; D008244:Lysophosphatidylcholines / Q000378:metabolism; D008297:Male; D010740:Phospholipases / Q000378:metabolism*; D012617:Sea Urchins / Q000201:enzymology*; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000201:enzymology*
chemical_list: D008244:Lysophosphatidylcholines; D010740:Phospholipases