Stromal Antigen 3 (STAG3)

STAG3 cDNAs encoding deduced proteins of 1,225 and 1,240 amino acids, respectively. Human STAG3 shares 75% sequence identity with the mouse Stag3 protein and approximately 45% similarity with human STAG1 and STAG2.

STAG3 contains an acidic C-terminal domain, a 28-amino acid domain conserved among mammalian stromalins, and an 86-amino acid domain, designated SCD, conserved among all stromalin family members. Northern blot analysis of human tissues revealed testis-specific expression of a 4.5-kb STAG3 transcript. In mouse tissues, the highest level of expression was found in male germ cells undergoing the first meiotic division.