Induction of capacitation in human spermatozoa in vitro by an endometrial sialic acid-binding protein |
| |
Authors: | Banerjee, Maitrayee Chowdhury, Mridula |
| |
Affiliation: | Indian Institute of Chemical Biology 4 Raja S.C.Mullick Road, Jadavpur, Calcutta 700 032, India |
| |
Abstract: | A Ca2+-dependent sialic acid-binding protein (SABP) of humanendometrium, which specifically bound to human sperm head plasmamembrane in vitro, was found to increase the percentage motilityand acrosome-reacted pattern of uncapacitated spermatozoa. Theprotein was synthesized in the endometrium and secreted intothe uterine fluid. This intra-uterine factor, which is apparentlyadvantageous in vitro in inducing human sperm capacitation,may play a significant role in promoting the postrelease maturationof ejaculated spermatozoa by enhancing 45Ca uptake into spermatozoaby a pathway which is insensitive to calcium-channel blockers.However, the 45Ca uptake could be enhanced on exposure to thedivalent cation ionophore A23187 and inhibited in the presenceof the calmodulin inhibitor trifluoperazine. The SABP also inducesan increase in intracellular Ca2+ in spermatozoa, as seen byFURA-2 AM studies. Furthermore, overlay studies show human SABPto be a Ca2+-binding protein. The data presented here suggestthat SABP induces invitro sperm capacitation and the subsequentacrosome reaction by increasing intracellular Ca2+ concentration. |
| |
Keywords: | acrosome reaction/calcium/human spermatozoa/motility |
本文献已被 Oxford 等数据库收录! |
|