Ultrastructural immunocytochemical evidence for actin in the acrosomal complex during spermiogenesis of the lizard tropidurus itambere (rodrigues, 1987) (reptilia: Tropiduridae)

Abstract

During spermiogenesis of the lizard Tropidurus itambere early developmental stages of the acrosomal complex have been analysed and new suggestions made as to their origin. Actin has been detected in the acrosomal granule and pro-acrosomal vesicle of spermatid, using an antibody for α-smooth muscle actin (monoclonal α-SMA). Intense marking also identified actin in two regions of the acrosomal complex; the subacrosomal cone and the perforatorium. The acrosomal and subacrosomal granules appear to participate to the formation of the perforatorium, while the pro-acrosomal vesicle is responsible for the formation of the subacrosomal cone. The results therefore endorse the view that, in lizards, the perforatorium and subacrosomal cone are homologous, in composition and probably also in function. © 2006 Taylor and Francis Group, LLC.