MTA2 modulates the enzymatic activity of the histone deacetylase core complex.The protein encoded by this gene is a member of the immunophilin protein family, which play a role in immunoregulation and basic cellular processes involving protein folding and trafficking. This encoded protein is a cis-trans prolyl isomerase that binds to the immunosuppressants FK506 and rapamycin. This gene is found to be deleted in Williams syndrome.