INVESTIGADORES
MAYORGA Luis Segundo
congresos y reuniones científicas
Título:
Morphological and molecular mechanisms involved in the acrosome swelling in human sperm
Autor/es:
SOSA CM; ZANETTI, MN; DE BLAS, G; MAYORGA, LS
Reunión:
Congreso; 48º SAIB; 2012
Institución organizadora:
SAIB
Resumen:
The acrosome reaction is an exocytic event essential for
fertilization. It requires the attachment of the outer acrosomal
membrane to the plasma membrane, the opening of fusion pores,
and the releasing the acrosomal contents together with hybrid
vesicles. In a previous report we have proposed that the swelling of
the acrosome and the deformation of the outer acrosomal membrane
is required for the process. By means of transmission electron
microscopy, in this communication we provide evidence for this
requirement: we show that all stimulators of the acrosome reaction
stimulate swelling and that swelling precedes the deformation of the
outer acrosomal membrane and the appearance of intraacrosomal
vesicles. According to observations in other models, the contact
between the outer acrosomal membrane and the plasma membrane
is part of the mechanism of store operated calcium channels
opening. However, by using specific inhibitors we show that
swelling is downstream the opening of these channels. Our results
indicate that acrosomal swelling is an essential part of acrosmal
exocytosis and that it is triggered by the influx of calcium through
store operated calcium channels in the plasma membrane.