F-Actin live cell staining with SiR-actin reveals specific dynamic changes during mouse sperm acrosomal exocytosis

DARSZON A; KRAPF D; PUGA MOLINA LC; LUQUE GM; BUFFONE MG; VELASCO FELIZ AG; VISCONTI PE; BALESTRINI PA; GERVASI MG; RAMIREZ GOMEZ HV; GUERRERO AO; GILIO N; XU X; TORRES RODRIGUEZ P; ROMAROWSKI A

Ciudad Autonoma de Buenos Aires

Congreso; Reunión Conjunta de Sociedades de Biociencias.; 2017

Acrosomal exocytosis (AE) is an absolute requisite for fertilization in mammals. This complex exocytic process is controlled by several players including changes in the actin cytoskeleton. Most studies to evaluate actin polymerization in mammalian sperm were performed using phalloidins, which are toxic and not capable of crossing the cell plasma membrane. As a result, it is not possible to use this approach to study this dynamic process in real time using live cells. SiR-actin is a novel membrane permeable fluorescent probe that binds to actin filaments in vivo. Using this new tool, we aimed to examine actin polymerization dynamics in live mouse sperm. We observed by image-based flow cytometry a capacitation-induced increase in polymerized actin levels (P