Rab3A and calmodulin regulate acrosomal exocytosis by mechanisms that do not require a direct interaction

FEBS Letters

Regazzi, R¹  De Blas, G²  Rodriguez, F²  Yunes, R²  Tomes, C²  Mayorga, L.S²  Michaut, M² 

[1] Institut de Biologie Cellulaire et de Morphologie, University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland;Laboratorio de Biologı́a Celular y Molecular, Instituto de Histologı́a y Embriologı́a (IHEM-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina

关键词: Rab3;    Calmodulin;    Acrosomal exocytosis;    Permeabilized cell;    Human spermatozoon;   

DOI  :  10.1016/S0014-5793(02)03102-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The interaction between Rab3A and calmodulin is necessary for the inhibitory effect of Rab3A in neuroendocrine cells. Contrastingly, Rab3A triggers the exocytosis known as acrosome reaction in permeabilized spermatozoa. Here we show that a Rab3A mutant that cannot bind calmodulin was fully capable of triggering acrosomal exocytosis. Additionally, calmodulin by itself abrogated the exocytosis triggered by Rab3A. The effect was observed with both the wild type protein and the calmodulin binding deficient mutant. Our results indicate that the inhibitory and stimulatory effects of Rab3A in different exocytic processes are mediated by different effectors.

【 授权许可】

Unknown