A species-specific sperm-activating peptide from the egg jelly of the sea urchin Diadema setosum

Abstract

1. 1. A species-specific sperm-activating peptide was isolated from the egg jelly of the sea urchin Diadema setosum and the amino acid sequence was determined as follows: ▪ 2. 2. The peptide caused significant increases of respiration rates and cyclic nucleotide concentrations in D. setosum spermatozoa as low as 10 −9 M. 3. 3. The addition of the peptide to D. setosum spermatozoa resulted in the appearance of a newly stained protein (mol. wt 128,000) on sodium dodecyl sulfate-polyacrylamide gels.