Cyclophilin A, or Peptidylprolyl isomerase A (cyclophilin A), is a human gene encoded by PPIA. It may also be known as: Peptidyl-prolyl cis-trans isomerase A; Cyclosporin A-binding protein; Rotamase A; PPIase A; CYPA; HEL-S-69p. The encoded protein is an enzyme with an amino acid length of 165 and a mass of 18.0 kDa. Cyclophilin A is a member of the Cyclophilin-type PPIase family, PPIase A subfamily. Homologs of this gene exist in other organisms, including: Mouse.