Involvement of ABCB1 and ABCC1 transporters in sea urchin Echinometra lucunter fertilization.
Fertilization is an ordered sequence of cellular interactions that promotes gamete fusion to form a new individual. Since the pioneering work of Oskar Hertwig conducted on sea urchins, echinoderms have contributed to the understanding of cellular and molecular aspects of the fertilization processes. Studies on sea urchin spermatozoa reported the involvement of a plasma membrane protein that belongs to the ABC proteins superfamily in the acrosome reaction. ABC transporters are expressed in membranes of eukaryotic and prokaryotic cells, and are associated with the transport of several compounds or ions across biomembranes. We aimed to investigate ABCB1 and ABCC1 transporter activity in sea urchin spermatozoa and their involvement in fertilization. Our results indicate that Echinometra lucunter spermatozoa exhibit a low intracellular calcein accumulation (18.5% stained cells); however, the ABC blockers reversin205, verapamil, and MK571 increased dye accumulation (93.0-96.6% stained cells). We also demonstrated that pharmacologically blocking ABCB1 and ABCC1 decreased spermatozoa fertilizing capacity (70% inhibition), and this phenotype was independent of extracellular calcium. These data suggest that functional spermatozoa ABCB1 and ABCC1 transporters are crucial for a successful fertilization. Additional studies must be performed to investigate the involvement of membrane lipid homeostasis in the fertilization process.
Departamento de Biologia Molecular, Universidade Federal da Paraíba, João Pessoa, Paraíba, Brazil.
Helena Lima
HL
Silva-Neta
Elis
E
Torrezan
Jocelmo Cássio
JC
de Araújo Leite
Tatiane
T
Santi-Gadelha
Luis Fernando
LF
Marques-Santos
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D018528:ATP-Binding Cassette Transporters / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000177:Acrosome / Q000378:metabolism; D020101:Acrosome Reaction; D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology; D005306:Fertilization / Q000187:drug effects*; D005452:Fluoresceins / Q000378:metabolism; D020024:Leukotriene Antagonists / Q000494:pharmacology; D008297:Male; D026901:Membrane Transport Proteins / Q000378:metabolism*; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D009842:Oligopeptides / Q000494:pharmacology; D027361:Organic Anion Transporters / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011422:Propionates / Q000494:pharmacology; D011804:Quinolines / Q000494:pharmacology; D012617:Sea Urchins / Q000187:drug effects / Q000378:metabolism*; D013094:Spermatozoa / Q000187:drug effects / Q000378:metabolism; D014700:Verapamil / Q000494:pharmacology
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D018528:ATP-Binding Cassette Transporters; D002121:Calcium Channel Blockers; D005452:Fluoresceins; D020024:Leukotriene Antagonists; D026901:Membrane Transport Proteins; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D009842:Oligopeptides; D027361:Organic Anion Transporters; D011422:Propionates; D011804:Quinolines; D014700:Verapamil; C120261:reversin 205; C059141:verlukast; C007740:fluorexon; C421109:multidrug resistance-associated protein 1