Pilot studies on the involvement of ubiquitin-proteasome system (UPS) in mammalian sperm capacitation

0463047 - BTÚ 2017 US eng C - Conference Paper (international conference)
Zigo, Michal - Kerns, K. - Šutovsky, M. - Šutovský, P.
Pilot studies on the involvement of ubiquitin-proteasome system (UPS) in mammalian sperm capacitation.
Book of abstracts of the 49th Annual meeting - Systems biology of Reproduction. Madison: Society for the Study of Reproduction, 2016 - (Murphy, B.), s. 78-78
[49th Annual meeting - Systems biology of Reproduction. San Diego (US), 16.07.2016-20.07.2016]
R&D Projects: GA MŠMT(CZ) ED 1.1.00/02.0109
Keywords : ubiqutin-proteasome system * sperm capacitation * sperm-zona pellucida interactions * flow cytometry
Subject RIV: CE - Biochemistry

Ubiquitination is a stable, reversible posttranslational modification of target proteins by covalent ligation of the small chaperone protein ubiquitin. Studies revealed the role of UPS in the regulation of fertilization. Employing differential sperm compartment fractionation and protein isolation approaches and conditions, proteins were isolated from the ejaculated and in vitro capacitated spermatozoa under UPS permissive conditions. After PAGE resolution, protein pattern differences were screened in ejaculated vs. capacitated spermatozoa, as these individual proteins are the prime candidate substrates of UPS during sperm capacitation. Most strikingly, lactadherin MFGE8, appears to be processed during the course of capacitation. Furthermore, proteasomal 19S regulatory particle subunit PSMD4 of 58 kDa was less abundant in capacitated spermatozoa, and a unique PSMD4 band of 74 kDa was detected in both ejaculated and capacitated spermatozoa extracted with TrX-100. Proteasomal inhibitors also prevented the detachment of acrosomal shrouds that is typically observed in a subpopulation of in vitro capacitating spermatozoa. These preliminary results support the proposed role of UPS in the sperm capacitation, while additional studies are underway.
Permanent Link: http://hdl.handle.net/11104/0262882