Sad-1 And Unc-84 Domain Containing Protein 3 (SUN3)

Sun3 is a novel member of the mammalian SUN protein family.Sun3 is a testis specific protein showing a postmeiotic expression profile. Previous studies described a short human SUN domain protein, SUN3, which was suggested to be expressed mainly in the testis. However, up to the present the actual expression pattern as well as its subcellular distribution within the cells naturally expressing SUN3 is not known. The corresponding protein consists of 320 amino acid residues with a calculated molecular weight of approx. 36,800 and a pI of about 7.67. On the amino acid level murine Sun3 shows 71% identity (78% similarity) to the previously described putative human SUN3. Sun3 expression correlates with sperm head formation.