N-Acetylated Alpha Linked Acidic Dipeptidase Like Protein 1 (NAALADL1)

The deduced 740-amino acid protein has a calculated molecular mass of 80.6 kD. NAALADL1 contains an N-terminal transmembrane domain, 2 putative catalytic domains, and 7 potential N-glycosylation sites. The first catalytic domain is similar to bacterial and yeast Zn(2+)-dependent peptidase domains, and the second is related to members of the alpha/beta-hydrolase fold family of proteins. NAALADL1 shares 35% and 37% amino acid identity with NAALADase I and NAALADase II (NAALAD2), respectively. Several NAALADL1 splice variants were also identified in small intestine, colon, and adult and fetal brain cDNA libraries. RT-PCR detected variable NAALADL1 expression, with highest levels in small intestine, spleen, and testis, and lowest levels in brain and muscle. NAALADL1 was also expressed in some subregions of adult brain.