FK506-binding protein 8 (38 kD FK506-binding protein homolog, FKBP8, FKBP38, FKBPR38)

Function: - constitutively inactive PPiase, which becomes active when bound to calmodulin & Ca⁺² - seems to act as a chaperone for BCL2, targets it to mitochondria & modulates its phosphorylation state - BCL2/FKBP8/calmodulin/Ca⁺² complex probably interferes with binding of BCL2 to its targets; active form of FKBP8 may thus play a role in the regulation of apoptosis - forms heterodimer with calmodulin - when activated by calmodulin & Ca⁺², interacts with the BH4 domain of BCL2 & weakly with BCLX isoform Bcl-X(L) - does not bind & inhibit calcineurin - interacts with HCV NS5A - binds the immunosuppressant FK506 only in its calmodulin/Ca⁺² activated form peptidylproline (omega=180) peptidylproline (omega=0) Cofactor: Ca⁺² Structure: - homomultimers or heteromultimers (putative) - contains 1 PPIase FKBP-type domain - contains 3 TPR repeats Compartment: mitochondrial membrane Expression: - widely expressed - highest levels seen in the brain

Properties

SIZE: entity length = 355 aa MW = 38 kD COMPARTMENT: mitochondria MOTIF: active site SITE: 63-147 tetratricopeptide repeat {167-200} tetratricopeptide repeat {218-251} tetratricopeptide repeat {252-285} MOTIF: Tyr phosphorylation site {Y265} transmembrane domain {333-353}

Database Correlations

OMIM 604840 UniProt Q14318 PFAM correlations ENZYME 5.2.1.8

References

UniProt :accession Q14318