Cytochrome P450 26B1 (EC 1.14.13.-) (Cytochrome P450 26A2) (Cytochrome P450 retinoic acid-inactivating 2) (Cytochrome P450RAI-2) (Retinoic acid-metabolizing cytochrome)
1_MLFEG 6_ LDLVS 11_ ALATL 16_ AACLV 21_ SVTLL 26_ LAVSQ 31_ QLWQL 36_ RWAAT 41_ RDKSC 46_ KLPIP 51_ KGSMG 56_ FPLIG 61_ ETGHW 66_ LLQGS 71_ GFQSS 76_ RREKY 81_ GNVFK 86_ THLLG 91_ RPLIR 96_ VTGAE 101_ NVRKI 106_ LMGEH 111_ HLVST 116_ EWPRS 121_ TRMLL 126_ GPNTV 131_ SNSIG 136_ DIHRN 141_ KRKVF 146_ SKIFS 151_ HEALE 156_ SYLPK 161_ IQLVI 166_ QDTLR 171_ AWSSH 176_ PEAIN 181_ VYQEA 186_ QKLTF 191_ RMAIR 196_ VLLGF 201_ SIPEE 206_ DLGHL 211_ FEVYQ 216_ QFVDN 221_ VFSLP 226_ VDLPF 231_ SGYRR 236_ GIQAR 241_ QILQK 246_ GLEKA 251_ IREKL 256_ QCTQG 261_ KDYLD 266_ ALDLL 271_ IESSK 276_ EHGKE 281_ MTMQE 286_ LKDGT 291_ LELIF 296_ AAYAT 301_ TASAS 306_ TSLIM 311_ QLLKH 316_ PTVLE 321_ KLRDE 326_ LRAHG 331_ ILHSG 336_ GCPCE 341_ GTLRL 346_ DTLSG 351_ LRYLD 356_ CVIKE 361_ VMRLF 366_ TPISG 371_ GYRTV 376_ LQTFE 381_ LDGFQ 386_ IPKGW 391_ SVMYS 396_ IRDTH 401_ DTAPV 406_ FKDVN 411_ VFDPD 416_ RFSQA 421_ RSEDK 426_ DGRFH 431_ YLPFG 436_ GGVRT 441_ CLGKH 446_ LAKLF 451_ LKVLA 456_ VELAS 461_ TSRFE 466_ LATRT 471_ FPRIT 476_ LVPVL 481_ HPVDG 486_ LSVKF 491_ FGLDS 496_ NQNEI 501_ LPETE 506_AMLSA
1: A cytochrome P450 monooxygenase involved in the metabolism of retinoates (RAs), the active metabolites of vitamin A, and critical signaling molecules in animals (PubMed:10823918, PubMed:22020119). RAs exist as at least four different isomers: all-trans-RA (atRA), 9-cis-RA, 13-cis-RA, and 9,13-dicis-RA, where atRA is considered to be the biologically active isomer, although 9-cis-RA and 13-cis-RA also have activity (Probable). Catalyzes the hydroxylation of atRA primarily at C-4 and C-18, thereby contributing to the regulation of atRA homeostasis and signaling (PubMed:10823918). Hydroxylation of atRA limits its biological activity and initiates a degradative process leading to its eventual elimination (PubMed:10823918, PubMed:22020119). Involved in the convertion of atRA to all-trans-4-oxo-RA. Can oxidize all-trans-13,14-dihydroretinoate (DRA) to metabolites which could include all-trans-4-oxo-DRA, all-trans-4-hydroxy-DRA, all-trans-5,8-epoxy-DRA, and all-trans-18-hydroxy-DRA (By similarity). Shows preference for the following substrates: atRA > 9-cis-RA > 13-cis-RA (PubMed:10823918, PubMed:22020119). Plays a central role in germ cell development: acts by degrading RAs in the developing testis, preventing STRA8 expression, thereby leading to delay of meiosis. Required for the maintenance of the undifferentiated state of male germ cells during embryonic development in Sertoli cells, inducing arrest in G0 phase of the cell cycle and preventing meiotic entry. Plays a role in skeletal development, both at the level of patterning and in the ossification of bone and the establishment of some synovial joints (PubMed:22019272). Essential for postnatal survival (By similarity)
2: Also has a significant activity in oxidation of tazarotenic acid and may therefore metabolize that xenobiotic in vivo