7-dehydrocholesterol reductase (7-DHC reductase) (EC 1.3.1.21) (Delta7-sterol reductase) (Sterol Delta(7)-reductase) (Sterol reductase SR-2)
1_MAAKS 6_ QPNIP 11_ KAKSL 16_ DGVTN 21_ DRTAS 26_ QGQWG 31_ RAWEV 36_ DWFSL 41_ ASVIF 46_ LLLFA 51_ PFIVY 56_ YFIMA 61_ CDQYS 66_ CALTG 71_ PVVDI 76_ VTGHA 81_ RLSDI 86_ WAKTP 91_ PITRK 96_ AAQLY 101_ TLWVT 106_ FQVLL 111_ YTSLP 116_ DFCHK 121_ FLPGY 126_ VGGIQ 131_ EGAVT 136_ PAGVV 141_ NKYQI 146_ NGLQA 151_ WLLTH 156_ LLWFA 161_ NAHLL 166_ SWFSP 171_ TIIFD 176_ NWIPL 181_ LWCAN 186_ ILGYA 191_ VSTFA 196_ MVKGY 201_ FFPTS 206_ ARDCK 211_ FTGNF 216_ FYNYM 221_ MGIEF 226_ NPRIG 231_ KWFDF 236_ KLFFN 241_ GRPGI 246_ VAWTL 251_ INLSF 256_ AAKQR 261_ ELHSH 266_ VTNAM 271_ VLVNV 276_ LQAIY 281_ VIDFF 286_ WNETW 291_ YLKTI 296_ DICHD 301_ HFGWY 306_ LGWGD 311_ CVWLP 316_ YLYTL 321_ QGLYL 326_ VYHPV 331_ QLSTP 336_ HAVGV 341_ LLLGL 346_ VGYYI 351_ FRVAN 356_ HQKDL 361_ FRRTD 366_ GRCLI 371_ WGRKP 376_ KVIEC 381_ SYTSA 386_ DGQRH 391_ HSKLL 396_ VSGFW 401_ GVARH 406_ FNYVG 411_ DLMGS 416_ LAYCL 421_ ACGGG 426_ HLLPY 431_ FYIIY 436_ MAILL 441_ THRCL 446_ RDEHR 451_ CASKY 456_ GRDWE 461_ RYTAA 466_VPYRL
1: Oxidoreductase that catalyzes the last step of the cholesterol synthesis pathway, which transforms cholesta-5,7-dien-3beta-ol (7-dehydrocholesterol,7-DHC) into cholesterol by reducing the C7-C8 double bond of its sterol core (PubMed:25637936, PubMed:38297129, PubMed:38297130, PubMed:9465114, PubMed:9634533). Can also metabolize cholesta-5,7,24-trien-3beta-ol (7-dehydrodemosterol, 7-DHD) to desmosterol, which is then metabolized by the Delta(24)-sterol reductase (DHCR24) to cholesterol (By similarity). Modulates ferroptosis (a form of regulated cell death driven by iron-dependent lipid peroxidation) through the metabolic breakdown of the anti-ferroptotic metabolites 7-DHC and 7-DHD which, when accumulated, divert the propagation of peroxyl radical-mediated damage from phospholipid components to its sterol core, protecting plasma and mitochondrial membranes from phospholipid autoxidation (PubMed:38297129, PubMed:38297130)
2: Component of the microsomal antiestrogen binding site (AEBS), a multiproteic complex at the ER membrane that consists of an association between cholestenol Delta-isomerase/EBP and DHCR7 (PubMed:15175332, PubMed:20615952). This complex is responsible for cholesterol-5,6-epoxide hydrolase (ChEH) activity, which consists in the hydration of cholesterol-5,6-epoxides (5,6-EC) into cholestane-3beta,5alpha,6beta-triol (CT) (PubMed:20615952). The precise role of each component of this complex has not been described yet (PubMed:20615952)