[a]Z1 is an alias for the gene, Centrosomal protein 131kDa, in humans. Other names include: Centrosomal protein of 131 kDa; 5-azacytidine-induced protein 1; Pre-acrosome localization protein 1; AZ1; ZA1. The encoded protein has an amino acid length of 1083 and a mass of 122.1 kDa. Other isoforms may exist. [a]Z1 is a member of the CEP131 family. This gene shares homology with other species, including: Mouse, Rat, Arabidopsis, Zebrafish, Frog.