Astacin Like Metallo Endopeptidase (ASTL)

The deduced 431-amino acid human protein contains an N-terminal signal peptide, a prodomain, a zinc-dependent metalloprotease domain, and a C-terminal extension that is likely to be heavily O-glycosylated. ASTL has all the conserved features of the astacin family of metalloproteases. Mouse Astl shares 78% amino acid identity with the human protein. The C-terminal extension is the most divergent region between mouse and human, and this region shows most divergence from other astacin family members. Expression of ASTL was below the level of detection by Northern blot analysis in all normal tissues examined; however, a 2.5-kb transcript was detected in leukemia and lymphoma cells of different origin. RT-PCR analysis detected ASTL expression in human and mouse ovary.