Expression of Fas-associated Factor 1 in the Developing Testis / 체질인류학회지

ABSTRACT

FAS associated factor 1 (FAF1) is a Fas-associating molecule, which enhances Fas mediated apoptosis. FAF1 gene is expressed most abundantly in the testis among the mouse organs. The aim of this study was to reveal the expression and the role of FAF1 in the developing testis. H-E stain and FAF1 immunohistochemistry were performed in the testis and epididymis of the E15.5 embryo, and 1, 2, and 8 week-old C57/BL6 mice. FAF1 was expressed in the testis from E 15.5 embryo to 8 week-old mice. Cell type of FAF1 positive cells was different among the developmental stage. Furthermore, cellular (cytoplasmic or nuclear) localization of FAF1 in the male germ cells was different during the developmental stage. FAF1 was expressed mainly in the nuclei of the germ cells 1 and 8 weeks after birth, when cell differentiation occurs actively in the testis. However, FAF1 was expressed in the cytoplasms of germ cells 2 weeks after birth, when apoptosis occurs maximally in the testis. Taken together, it can be suggested FAF1 expressed in male germ cells in the testis. FAF1 might be involved in regulation of the cellular function during spermatogenic cell differentiation and apoptosis in the testis.