Peptidylprolyl Isomerase E (PPIE)

Peptidyl-prolyl cis-trans isomerase E is  a member of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and accelerate the folding of proteins. This protein contains a highly conserved cyclophilin (CYP) domain as well as an RNA-binding domain. It was shown to possess PPIase and protein folding activities and also exhibit RNA-binding activity. Three alternatively spliced transcript variants encoding distinct isoforms have been observed.The PPIase activity of CYP33 is inhibited by CsA with kinetics similar to other CYPs. Northern blotting of T-cell mRNA revealed expression of a low abundance 1.6-kb CYP33 transcript.