RELEVANCE OF CYSTEIN-RICH SECRETORY PROTEINS FOR MALE FERTILITY

WEIGEL MUÑOZ, MARIANA; SULZYK, VALERIA ; CURCI, LUDMILA; CUASNICU, PATRICIA S

Congreso; REUNIÓN ANUAL DE SOCIEDADES DE BIOCIENCIA 2019; 2019

RELEVANCE OF CYSTEIN-RICH SECRETORY PROTEINS FOR MALE FERTILITYLudmila CURCI | Valeria SULZYK | Mariana WEIGEL MUÑOZ | Patricia CUASNICÚCysteine-rich secretory protein (CRISP) 1, 2, 3 and 4 are mainly expressed in the reproductive tract and have key roles in mammalian fertilization. In spite of this, knockout (KO) mice for each individual protein are fertile whereas double KO (DKO) CRISP1/CRISP4 are subfertile, suggesting the existence of compensatory mechanisms between homologous CRISP family members. Recent results from our lab revealed that DKO CRISP1/CRISP3 are also subfertile. Based on this, the aim of the present work was to investigate the mechanisms underlying the lower fertility rates observed in these animals. In order to do this, we first analyzed the percentage of fertilized eggs recovered from the ampulla of superovulated females mated by DKO1/3 or control males. As no significant differences between groups in these in vivo fertilization rates were observed, the recovered fertilized oocytes from both groups were incubated in vitro for additional 5 days to analyze their subsequent development. Results showed that the percentage of oocytes from mutant males that reached the blastocyst stage under these conditions was significantly lower than that corresponding to controls, suggesting that CRISP1 and CRISP3 may be important for early embryo development. To investigate potential functional deficiencies in mutant sperm that could be responsible for these observations, DKO1/3 and control sperm were co-incubated in vitro with eggs (surrounded by both cumulus oophorus and zona pellucida or denuded of these coats) and the percentage of fertilized eggs determined. Results revealed significantly lower fertilization rates for mutant than for control sperm, confirming defects in mutant sperm fertilizing ability. Together, these observations support the role of CRISP1 and CRISP3 for male fertility and fertilization and contribute to a better understanding of how paternal factors could impact on embryo development.