Localization of SNAREs, NSF and Caveolin 1 in human spermatozoa: relationship with seminal parameters.

Membrane fusion is a very important process in gametes. The mechanism of membrane fusion during the AR has been proposed to involve SNAREs. Our aim is to quantify patterns of localization of Caveolin 1, SNAREs (Syntaxin 1A, Syntaxin 2 and VAMP 1) and NSF on human sperm, to determine how the differential distribution of these proteins might be interdependent and to evaluate if this distribution is related with seminal parameters. These proteins are present in different regions of the head of human sperm: anterior, equatorial and posterior regions and that Syntaxin 2 and Syntaxin 1A had a slightly different pattern of labelling. The presence and localization of SNAREs, NSF and Caveolin 1 do not correlate with seminal parameters. There is significant correlation between NSF and SNAREs, which may indicate a cooperation of these proteins in membrane fusion mechanisms of human sperm.