cyclophilin H (peptidyl-prolyl cis-trans isomerase H, PPIase H, rotamase H, U-snRNP-associated cyclophilin SnuCyp-20, USA-CYP, small nuclear ribonucleoprotein [snRNP] particle-specific cyclophilin H, PPIH, CYP20, CYPH)

Function

• PPIases accelerate the folding of proteins
• catalyzes cis-trans isomerization of proline imidic peptide bonds in oligopeptides
• participates in pre-mRNA splicing
• may play a role in assembly of the U4/U5/U6 tri-snRNP complex
• may act as a chaperone
• interacts directly with PRPF4
• part of a heteromeric complex containing PPIH, PRPF3 & PRPF4 that is stable in the absence of RNA; this complex interacts with the U4/U5/U6 tri-snRNP complex
• heterodimer with PRPF18
• inhibited by cyclosporin A

peptidylproline (omega=180) <--> peptidylproline (omega=0)

Structure

• belongs to the cyclophilin-type PPIase family, PPIase H subfamily
• contains 1 PPIase cyclophilin-type domain

Compartment

• nucleus speckle, cytoplasm
• colocalizes with spliceosomal snRNPs
• small proportion may also be cytoplasmic

More general terms

• cyclophilin
• chaperonin; chaperone

Database

• OMIM: https://mirror.omim.org/entry/606095
• UniProt: http://www.uniprot.org/uniprot/O43447.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=10465