5i7q

Structural highlights

Function

FKBX_ECOLI PPIases accelerate the folding of proteins. Substrate specificity investigated with 'Suc-Ala-Xaa-Pro-Phe-4-nitroanilide' where Xaa is the amino acid tested, was found to be Phe > Leu >> Ile > Lys = Ala > Trp > His >> Gln.FKB1A_HUMAN Keeps in an inactive conformation TGFBR1, the TGF-beta type I serine/threonine kinase receptor, preventing TGF-beta receptor activation in absence of ligand. Recruites SMAD7 to ACVR1B which prevents the association of SMAD2 and SMAD3 with the activin receptor complex, thereby blocking the activin signal. May modulate the RYR1 calcium channel activity. PPIases accelerate the folding of proteins. It catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides.^{[1] [2]}

References

1. ↑ Chen YG, Liu F, Massague J. Mechanism of TGFbeta receptor inhibition by FKBP12. EMBO J. 1997 Jul 1;16(13):3866-76. PMID:9233797 doi:10.1093/emboj/16.13.3866
2. ↑ Yamaguchi T, Kurisaki A, Yamakawa N, Minakuchi K, Sugino H. FKBP12 functions as an adaptor of the Smad7-Smurf1 complex on activin type I receptor. J Mol Endocrinol. 2006 Jun;36(3):569-79. PMID:16720724 doi:10.1677/jme.1.01966