Amy1 Associated Protein Expressed In Testis (AAT1)

The longest variant, AAT1-alpha, encodes a deduced 98-amino acid protein. The shorter transcripts, AAT1-beta and AAT1-gamma, encode identical proteins that correspond to the 31 C-terminal amino acids of AAT1-alpha. Western blot analysis of mouse testis detected endogenous Aat1-alpha at an apparent molecular mass of 10.8 kD. AAT1 was expressed in all mouse, rat, and human spermatogenesis-related tissues and cell lines examined. Expression was also detected in all cell lines of non-testis origin examined. In situ hybridization and immunohistochemical analysis of mouse testis detected Aat1 during all stages of spermatogenesis and in Leydig cells.Aat1 was also detected in the neck region of mature sperm. AAT1 colocalized with AMY1 in mitochondria in transfected human and mouse cells.