Peculiar subcellular localization of Fas antigen in human and mouse spermatozoa

✍ Scribed by Donatella Starace; Barbara Muciaccia; Emanuela Morgante; Matteo A. Russo; Simona Pensini; Angela D'agostino; Paola De Cesaris; Antonio Filippini; Elio Ziparo; Anna Riccioli

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 265 KB
• Volume: 72
• Category: Article
• ISSN: 1059-910X
• DOI: 10.1002/jemt.20700

✦ Synopsis

Abstract

The highly polarized structure and function of mammalian spermatozoa dictate that these cells compartmentalize specific metabolic and signaling pathways to regions where they are needed. Fas was initially identified as membrane receptor for pro‐apoptotic signals, has been recently recognized as a molecule with pleiotropic functions. In this article, we provide evidence of a peculiar Fas localization: it is closely associated to the perinucleus, mainly at the level of the inner acrosomal membrane, as well as in the inner compartment of mitochondria. Immunoelectron microscopy and Western blot analysis indicated that intracellular Fas was associated with mitochondria in mouse epididymal spermatozoa. Accordingly, also in human ejaculated sperm, immunofluorescence analysis showed Fas localized in the middle piece of sperm flagellum where mitochondria are grouped. The potential functional implications of these findings are discussed. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.