FAK regulates actin polymerization during sperm capacitation via the ERK2/GEF-H1/RhoA signaling pathway.
J Cell Sci
; 133(8)2020 04 28.
Article
em En
| MEDLINE
| ID: mdl-32107290
ABSTRACT
Actin polymerization is a crucial process during sperm capacitation. We have recently described the participation of FAK during actin polymerization in guinea pig spermatozoa. However, the mechanism by which FAK mediates these processes is unknown. Our previous data have shown that MAPK1 (hereafter referred to as ERK2) is activated during the first minutes of capacitation, and inhibition of ERK2 blocked actin polymerization and the acrosome reaction. In this current study, we found that FAK is involved in ERK2 activation - as FAK was phosphorylated at tyrosine residue 925 and bound to Grb2 - and that inhibition of FAK results in a significant decrease of ERK2 activation. We also confirmed the presence of Rho guanine nucleotide exchange factor 2 (ARHGEF2, hereafter referred to as GEF-H1), which is able to associate with RhoA during capacitation. RhoA activation and its participation in actin polymerization were also analyzed. Inhibition of FAK or ERK1/2 impeded GEF-H1 phosphorylation, RhoA activation, and the association between GEF-H1 and RhoA. Finally, we observed the presence of fibronectin on the sperm surface, its role in sperm-sperm interaction as well as participation of ß-integrin in the activation of ERK2. Our results show that the signaling pathway downstream of fibronectin, via integrin, FAK, Grb2, MEK1/2, ERK2, GEF-H1 and RhoA regulates the actin polymerization associated with spermatozoa capacitation.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Capacitação Espermática
/
Actinas
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Proteína-Tirosina Quinases de Adesão Focal
Limite:
Animals
Idioma:
En
Revista:
J Cell Sci
Ano de publicação:
2020
Tipo de documento:
Article