Protein disulfide-isomerase (PDI) (EC 5.3.4.1) (Cellular thyroid hormone-binding protein) (Prolyl 4-hydroxylase subunit beta) (p55)
1_MLRRA 6_ LLCLA 11_ VAALV 16_ RADAP 21_ EEEDH 26_ VLVLR 31_ KSNFA 36_ EALAA 41_ HKYLL 46_ VEFYA 51_ PWCGH 56_ CKALA 61_ PEYAK 66_ AAGKL 71_ KAEGS 76_ EIRLA 81_ KVDAT 86_ EESDL 91_ AQQYG 96_ VRGYP 101_ TIKFF 106_ RNGDT 111_ ASPKE 116_ YTAGR 121_ EADDI 126_ VNWLK 131_ KRTGP 136_ AATTL 141_ PDGAA 146_ AESLV 151_ ESSEV 156_ AVIGF 161_ FKDVE 166_ SDSAK 171_ QFLQA 176_ AEAID 181_ DIPFG 186_ ITSNS 191_ DVFSK 196_ YQLDK 201_ DGVVL 206_ FKKFD 211_ EGRNN 216_ FEGEV 221_ TKENL 226_ LDFIK 231_ HNQLP 236_ LVIEF 241_ TEQTA 246_ PKIFG 251_ GEIKT 256_ HILLF 261_ LPKSV 266_ SDYDG 271_ KLSNF 276_ KTAAE 281_ SFKGK 286_ ILFIF 291_ IDSDH 296_ TDNQR 301_ ILEFF 306_ GLKKE 311_ ECPAV 316_ RLITL 321_ EEEMT 326_ KYKPE 331_ SEELT 336_ AERIT 341_ EFCHR 346_ FLEGK 351_ IKPHL 356_ MSQEL 361_ PEDWD 366_ KQPVK 371_ VLVGK 376_ NFEDV 381_ AFDEK 386_ KNVFV 391_ EFYAP 396_ WCGHC 401_ KQLAP 406_ IWDKL 411_ GETYK 416_ DHENI 421_ VIAKM 426_ DSTAN 431_ EVEAV 436_ KVHSF 441_ PTLKF 446_ FPASA 451_ DRTVI 456_ DYNGE 461_ RTLDG 466_ FKKFL 471_ ESGGQ 476_ DGAGD 481_ DDDLE 486_ DLEEA 491_ EEPDM 496_ EEDDD 501_QKAVK
1: This multifunctional protein catalyzes the formation, breakage and rearrangement of disulfide bonds. At the cell surface, seems to act as a reductase that cleaves disulfide bonds of proteins attached to the cell. May therefore cause structural modifications of exofacial proteins. Inside the cell, seems to form/rearrange disulfide bonds of nascent proteins. At high concentrations and following phosphorylation by FAM20C, functions as a chaperone that inhibits aggregation of misfolded proteins (PubMed:32149426). At low concentrations, facilitates aggregation (anti-chaperone activity). May be involved with other chaperones in the structural modification of the TG precursor in hormone biogenesis. Also acts as a structural subunit of various enzymes such as prolyl 4-hydroxylase and microsomal triacylglycerol transfer protein MTTP. Receptor for LGALS9; the interaction retains P4HB at the cell surface of Th2 T helper cells, increasing disulfide reductase activity at the plasma membrane, altering the plasma membrane redox state and enhancing cell migration (PubMed:21670307)