Proteasome alpha 7, PSMA7, is a multicatalytic proteinase complex which is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. PSMA7, belonged to the peptidase T1A family, is a 20S core alpha subunit of proteasome. This protein was found to interact specifically with two subdomains of HIF-1alpha and inhibited the transactivation function of HIF-1alpha under both normoxic and hypoxia-mimicking conditions.