IBYME   02675
INSTITUTO DE BIOLOGIA Y MEDICINA EXPERIMENTAL
Unidad Ejecutora - UE
artículos
Título:
Molecular mechanisms involved in mammalian sperm-egg interactions: Participation of CRISP (Cysteine-Rich Secretory Proteins) family members
Autor/es:
COHEN DJ, MALDERA JA, WEIGEL MUÑOZ M, ERNESTO JI Y CUASNICU PS
Revista:
BIOLOGICAL RESEARCH
Editorial:
SOC BIOLGIA CHILE
Referencias:
Año: 2011 vol. 44 p. 135 - 138
ISSN:
0716-9760
Resumen:
Epididymal protein CRISPI is a member of the CRISP (Cysteine-RIch
Secretory proteins) family and is involved in sperm-egg fusion through
its interaction with complementary sites on the egg surface. Results
from our laboratory have shown that this binding ability resides in a
12-amino-acid region corresponding to a highly conserved motif of the
CRISP family, named Signature 2 (S2). In addition to this, our results
revealed that CRISP1 could also be involved in the previous step of
sperm binding to the zona pellucida, identifying a novel role for this
protein in fertilization. As another approach to elucidate the
participation of CRISP1 in fertilization, a mouse line containing a
targeted disruption of CRISP1 was generated. Although CRISP1-deficient
mice exhibited normal fertility, CRISP1-defficient sperm presented a
decreased level of protein tyrosine phosphorylation during capacitation,
and an impaired ability to fertilize both zona-intact and zona-free
eggs in vitro, confirming the proposed roles for the protein in
fertilization. Evidence obtained in our laboratory indicated that
testicular CRISP2 would also be involved in sperm-egg fusion.
Competition assays between CRISP1 and CRISP2, as well as the comparison
of their corresponding S2 regions, suggest that both proteins bind to
common complementary sites in the egg. Together, these results suggest a
functional cooperation between CRISP1 and CRISP2 to ensure the success
of fertilization.