title: The charged milieu: a major player in fertilization reactions.
abstract: In previous studies, we have found that negatively charged, but not uncharged, amino acids and sugars block sea urchin fertilization. These studies were developed from modeling work in non-living systems using derivatized agarose beads that suggested that charge-charge bonding may control at least some adhesive interactions. In the present study, the effects of positively charged, negatively charged and uncharged molecules were examined in the sea urchin sperm-egg system in over 300 individual trials. The results indicate that depending on the specific molecules utilized, both sperm and egg are exquisitely sensitive to charged but not uncharged molecules and to pH changes in sea water caused by some of the charged molecules. It is shown that egg activation, as well as sperm motility and sperm-egg interactions, can be affected by charged molecules. One compound, fructose-1-phosphate blocked fertilization in S. purpuratus sea urchins but not in Lytechinus pictus sea urchins. These findings indicate that charge alone cannot explain all the results. In this case, the presence of a ketone instead of an aldehyde group indicates that species-specific components may control fertilization reactions. The present study is a comprehensive survey of the effects of charge, pH and molecular structure on the fertilization activation continuum in a model system of sea urchins.
authors.affiliation: Department of Biology and Center for Cancer and Developmental Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA.
authors.forename: Marcela
authors.initials: M
authors.lastname: Maldonado
authors.forename: Gayani
authors.initials: G
authors.lastname: Weerasinghe
authors.forename: Fabienne
authors.initials: F
authors.lastname: Ambroise
authors.forename: Edward
authors.initials: E
authors.lastname: Yamoah
authors.forename: Monica
authors.initials: M
authors.lastname: Londono
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Pelayo
authors.forename: Melina
authors.initials: M
authors.lastname: Grigorian
authors.forename: Steven B
authors.initials: SB
authors.lastname: Oppenheimer
mesh_terms: D000596:Amino Acids / Q000494:pharmacology*; D000818:Animals; D001120:Arginine / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D005260:Female; D005306:Fertilization / Q000187:drug effects*; D005944:Glucosamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D019298:Glucose-6-Phosphate / Q000031:analogs & derivatives* / Q000494:pharmacology; D006600:Hexosephosphates / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D008297:Male; D009005:Monosaccharides / Q000494:pharmacology; D010768:Phosphoserine / Q000494:pharmacology; D010769:Phosphothreonine / Q000494:pharmacology; D012267:Ribosemonophosphates / Q000494:pharmacology; D012617:Sea Urchins; D012623:Seawater / Q000737:chemistry; D013081:Sperm Motility / Q000187:drug effects; D013403:Sugar Phosphates / Q000494:pharmacology*; D015032:Zinc / Q000494:pharmacology
chemical_list: D000596:Amino Acids; D006600:Hexosephosphates; D009005:Monosaccharides; D012267:Ribosemonophosphates; D013403:Sugar Phosphates; D010769:Phosphothreonine; C031154:ribose 1-phosphate; D010768:Phosphoserine; C001293:glucosamine 6-phosphate; D000001:Calcimycin; D019298:Glucose-6-Phosphate; C046905:glucosamine 6-O-sulfate; D001120:Arginine; D015032:Zinc; D005944:Glucosamine; D002118:Calcium