title: Epididymal protein CRISP1 plays different roles during the fertilization process.
abstract: Rat epididymal CRISP1, the first described member of the evolutionarily  conserved Cysteine-RIch Secretory Protein (CRISP) family, is expressed in the  proximal regions of the epididymis and associates with the sperm during  epididymal transit. Evidence indicates the existence of 2 populations of  CRISP1 in spermatozoa: a major one, loosely bound, which is released during  capacitation and, therefore, proposed as a decapacitating factor; and a minor  one, strongly associated with spermatozoa that remains on the cells after  capacitation and is proposed to participate in gamete interaction. Originally  localized to the dorsal region of capacitated sperm, CRISP1 migrates to the  equatorial segment with capacitation and acrosome reaction. Consistent with  these localizations, in vitro fertilization experiments support the  involvement of CRISP1 in the first step of sperm-zona pellucida (ZP)  interaction and subsequent gamete fusion through its interaction with  egg-complementary sites. The potential roles of CRISP1 in capacitation and  fertilization have been further supported by the finding that capacitated  spermatozoa from CRISP1 "knockout" animals exhibit low levels of  protein tyrosine phosphorylation and have an impaired ability to fertilize  zona-intact and zona-free eggs in vitro. Moreover, recent evidence from mutant  spermatozoa reveals that CRISP1 mediates the stage of sperm binding to the ZP.  Altogether, these observations support the view that CRISP1 is a  multifunctional protein playing different roles during fertilization through  its different associations with and localizations on spermatozoa. We believe  these results contribute to a better understanding of the molecular mechanisms  involved in both the fertilization process and the acquisition of  sperm-fertilizing ability that occurs during epididymal maturation.
authors: Instituto de Biología y Medicina Experimental/CONICET, Vuelta de Obligado 2490, Buenos Aires, Argentina.
authors: Débora J
authors: DJ
authors: Cohen
authors: Julieta A
authors: JA
authors: Maldera
authors: Gustavo
authors: G
authors: Vasen
authors: Juan I
authors: JI
authors: Ernesto
authors: Mariana Weigel
authors: MW
authors: Muñoz
authors: María A
authors: MA
authors: Battistone
authors: Patricia S
authors: PS
authors: Cuasnicú
mesh_terms: D000818:Animals; D004822:Epididymis / Q000378:metabolism*; D005306:Fertilization; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D051381:Rats; D013075:Sperm Capacitation; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000378:metabolism; D015044:Zona Pellucida / Q000378:metabolism
chemical_list: C103538:CRISP1 protein, human; C486321:Crisp1 protein, mouse; C486320:Crisp3 protein, rat; D008562:Membrane Glycoproteins