ID   CYB5_RABIT              Reviewed;         134 AA.
AC   P00169; Q28726;
DT   21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT   23-JAN-2007, sequence version 4.
DT   27-MAR-2024, entry version 166.
DE   RecName: Full=Cytochrome b5;
GN   Name=CYB5A; Synonyms=CYB5;
OS   Oryctolagus cuniculus (Rabbit).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Euarchontoglires; Glires; Lagomorpha; Leporidae; Oryctolagus.
OX   NCBI_TaxID=9986;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
RX   PubMed=3222252;
RA   Dariush N., Fisher C.W., Steggles A.W.;
RT   "The nucleotide sequence of rabbit liver cytochrome b5 mRNA.";
RL   Protein Seq. Data Anal. 1:351-353(1988).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 2).
RC   STRAIN=New Zealand white;
RX   PubMed=1627141; DOI=10.1016/0006-291x(92)91704-t;
RA   Takamatsu H., Kozutsumi Y., Suzuki A., Kawasaki T.;
RT   "Molecular cloning of rabbit cytochrome b5 genes: evidence for the
RT   occurrence of two separate genes encoding the soluble and microsomal
RT   forms.";
RL   Biochem. Biophys. Res. Commun. 185:845-851(1992).
RN   [3]
RP   PROTEIN SEQUENCE OF 9-46 AND 50-91.
RX   PubMed=5709273; DOI=10.1093/oxfordjournals.jbchem.a128954;
RA   Tsugita A., Kobayashi M., Kajihara T., Hagihara B.;
RT   "Primary structure of rabbit liver cytochrome b5.";
RL   J. Biochem. 64:727-730(1968).
RN   [4]
RP   PROTEIN SEQUENCE OF 7-8 AND 47-49.
RX   PubMed=5272324; DOI=10.1073/pnas.67.1.442;
RA   Tsugita A., Kobayashi M., Tani S., Kyo S., Rashid M.A., Yoshida Y.,
RA   Kajihara T., Hagihara B.;
RT   "Comparative study of the primary structures of cytochrome b5 from four
RT   species.";
RL   Proc. Natl. Acad. Sci. U.S.A. 67:442-447(1970).
RN   [5]
RP   PROTEIN SEQUENCE OF 5-98.
RX   PubMed=5506260; DOI=10.1016/s0021-9258(18)62788-7;
RA   Ozols J.;
RT   "Amino acid sequence of rabbit liver microsomal cytochrome b5.";
RL   J. Biol. Chem. 245:4863-4874(1970).
RN   [6]
RP   PROTEIN SEQUENCE OF 92-134.
RX   PubMed=500581; DOI=10.1093/oxfordjournals.jbchem.a132606;
RA   Kondo K., Tajima S., Sato R., Narita K.;
RT   "Primary structure of the membrane-binding segment of rabbit cytochrome
RT   b5.";
RL   J. Biochem. 86:1119-1128(1979).
RN   [7]
RP   PROTEIN SEQUENCE OF 99-134.
RX   PubMed=7354043; DOI=10.1016/s0021-9258(19)86065-9;
RA   Takagaki Y., Gerber G.E., Nihei K., Khorana H.G.;
RT   "Amino acid sequence of the membranous segment of rabbit liver cytochrome
RT   b5. Methodology for separation of hydrophobic peptides.";
RL   J. Biol. Chem. 255:1536-1541(1980).
RN   [8]
RP   PROTEIN SEQUENCE OF 2-11, AND ACETYLATION AT ALA-2.
RX   PubMed=2752049; DOI=10.1016/0167-4838(89)90143-x;
RA   Ozols J.;
RT   "Structure of cytochrome b5 and its topology in the microsomal membrane.";
RL   Biochim. Biophys. Acta 997:121-130(1989).
RN   [9]
RP   STRUCTURE BY NMR OF 7-100.
RX   PubMed=10651812; DOI=10.1046/j.1432-1327.2000.01054.x;
RA   Banci L., Bertini I., Rosato A., Scacchieri S.;
RT   "Solution structure of oxidized microsomal rabbit cytochrome b5 factors
RT   determining the heterogeneous binding of the heme.";
RL   Eur. J. Biochem. 267:755-766(2000).
CC   -!- FUNCTION: Cytochrome b5 is a membrane-bound hemoprotein functioning as
CC       an electron carrier for several membrane-bound oxygenases.
CC   -!- SUBCELLULAR LOCATION: Endoplasmic reticulum membrane; Single-pass
CC       membrane protein; Cytoplasmic side. Microsome membrane; Single-pass
CC       membrane protein; Cytoplasmic side.
CC   -!- ALTERNATIVE PRODUCTS:
CC       Event=Alternative splicing; Named isoforms=2;
CC       Name=1; Synonyms=Liver, Membrane-bound;
CC         IsoId=P00169-1; Sequence=Displayed;
CC       Name=2; Synonyms=Erythrocyte, Cytoplasmic;
CC         IsoId=P00169-2; Sequence=VSP_001244, VSP_001245;
CC   -!- SIMILARITY: Belongs to the cytochrome b5 family. {ECO:0000305}.
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DR   EMBL; M24844; AAB03878.1; -; mRNA.
DR   EMBL; D10901; BAA01712.1; -; mRNA.
DR   PIR; JN0316; JN0316.
DR   PIR; S03373; CBRB5.
DR   RefSeq; NP_001164734.1; NM_001171263.1. [P00169-2]
DR   RefSeq; NP_001164735.1; NM_001171264.1. [P00169-1]
DR   RefSeq; XP_017199148.1; XM_017343659.1. [P00169-1]
DR   PDB; 1DO9; NMR; -; A=6-99.
DR   PDB; 2M33; NMR; -; A=1-134.
DR   PDBsum; 1DO9; -.
DR   PDBsum; 2M33; -.
DR   AlphaFoldDB; P00169; -.
DR   BMRB; P00169; -.
DR   SMR; P00169; -.
DR   STRING; 9986.ENSOCUP00000013951; -.
DR   iPTMnet; P00169; -.
DR   PaxDb; 9986-ENSOCUP00000013951; -.
DR   Ensembl; ENSOCUT00000016229.4; ENSOCUP00000013951.2; ENSOCUG00000016235.4. [P00169-1]
DR   Ensembl; ENSOCUT00000045010.1; ENSOCUP00000028877.1; ENSOCUG00000016235.4. [P00169-2]
DR   GeneID; 100328912; -.
DR   GeneID; 100328915; -.
DR   KEGG; ocu:100328912; -.
DR   eggNOG; KOG0537; Eukaryota.
DR   GeneTree; ENSGT00940000156770; -.
DR   HOGENOM; CLU_102602_3_3_1; -.
DR   InParanoid; P00169; -.
DR   OMA; FLNWILP; -.
DR   OrthoDB; 2712490at2759; -.
DR   TreeFam; TF314537; -.
DR   EvolutionaryTrace; P00169; -.
DR   Proteomes; UP000001811; Chromosome 9.
DR   Bgee; ENSOCUG00000016235; Expressed in liver and 17 other cell types or tissues.
DR   GO; GO:0005829; C:cytosol; IEA:Ensembl.
DR   GO; GO:0005789; C:endoplasmic reticulum membrane; IEA:UniProtKB-SubCell.
DR   GO; GO:0019899; F:enzyme binding; IEA:Ensembl.
DR   GO; GO:0020037; F:heme binding; IEA:InterPro.
DR   GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR   Gene3D; 3.10.120.10; Cytochrome b5-like heme/steroid binding domain; 1.
DR   InterPro; IPR001199; Cyt_B5-like_heme/steroid-bd.
DR   InterPro; IPR036400; Cyt_B5-like_heme/steroid_sf.
DR   InterPro; IPR018506; Cyt_B5_heme-BS.
DR   PANTHER; PTHR19359; CYTOCHROME B5; 1.
DR   PANTHER; PTHR19359:SF126; CYTOCHROME B5; 1.
DR   Pfam; PF00173; Cyt-b5; 1.
DR   PRINTS; PR00363; CYTOCHROMEB5.
DR   SMART; SM01117; Cyt-b5; 1.
DR   SUPFAM; SSF55856; Cytochrome b5-like heme/steroid binding domain; 1.
DR   PROSITE; PS00191; CYTOCHROME_B5_1; 1.
DR   PROSITE; PS50255; CYTOCHROME_B5_2; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Acetylation; Alternative splicing; Direct protein sequencing;
KW   Electron transport; Endoplasmic reticulum; Heme; Iron; Membrane;
KW   Metal-binding; Microsome; Reference proteome; Transmembrane;
KW   Transmembrane helix; Transport.
FT   INIT_MET        1
FT                   /note="Removed"
FT                   /evidence="ECO:0000269|PubMed:2752049"
FT   CHAIN           2..134
FT                   /note="Cytochrome b5"
FT                   /id="PRO_0000166013"
FT   TRANSMEM        109..131
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   DOMAIN          9..85
FT                   /note="Cytochrome b5 heme-binding"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00279"
FT   BINDING         44
FT                   /ligand="heme"
FT                   /ligand_id="ChEBI:CHEBI:30413"
FT                   /ligand_part="Fe"
FT                   /ligand_part_id="ChEBI:CHEBI:18248"
FT                   /note="axial binding residue"
FT   BINDING         68
FT                   /ligand="heme"
FT                   /ligand_id="ChEBI:CHEBI:30413"
FT                   /ligand_part="Fe"
FT                   /ligand_part_id="ChEBI:CHEBI:18248"
FT                   /note="axial binding residue"
FT   MOD_RES         2
FT                   /note="N-acetylalanine"
FT                   /evidence="ECO:0000269|PubMed:2752049"
FT   MOD_RES         7
FT                   /note="N6-acetyllysine"
FT                   /evidence="ECO:0000250|UniProtKB:P56395"
FT   MOD_RES         10
FT                   /note="N6-acetyllysine"
FT                   /evidence="ECO:0000250|UniProtKB:P56395"
FT   MOD_RES         19
FT                   /note="N6-acetyllysine"
FT                   /evidence="ECO:0000250|UniProtKB:P56395"
FT   VAR_SEQ         98
FT                   /note="T -> P (in isoform 2)"
FT                   /evidence="ECO:0000303|PubMed:1627141"
FT                   /id="VSP_001244"
FT   VAR_SEQ         99..134
FT                   /note="Missing (in isoform 2)"
FT                   /evidence="ECO:0000303|PubMed:1627141"
FT                   /id="VSP_001245"
FT   CONFLICT        62
FT                   /note="N -> D (in Ref. 3; AA sequence and 5; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        104
FT                   /note="D -> N (in Ref. 6; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   STRAND          10..12
FT                   /evidence="ECO:0007829|PDB:2M33"
FT   HELIX           14..17
FT                   /evidence="ECO:0007829|PDB:1DO9"
FT   TURN            18..20
FT                   /evidence="ECO:0007829|PDB:2M33"
FT   STRAND          22..25
FT                   /evidence="ECO:0007829|PDB:2M33"
FT   STRAND          27..36
FT                   /evidence="ECO:0007829|PDB:1DO9"
FT   HELIX           38..40
FT                   /evidence="ECO:0007829|PDB:1DO9"
FT   TURN            41..43
FT                   /evidence="ECO:0007829|PDB:1DO9"
FT   STRAND          44..46
FT                   /evidence="ECO:0007829|PDB:1DO9"
FT   HELIX           49..53
FT                   /evidence="ECO:0007829|PDB:1DO9"
FT   TURN            54..56
FT                   /evidence="ECO:0007829|PDB:1DO9"
FT   HELIX           60..66
FT                   /evidence="ECO:0007829|PDB:1DO9"
FT   HELIX           70..79
FT                   /evidence="ECO:0007829|PDB:1DO9"
FT   STRAND          80..84
FT                   /evidence="ECO:0007829|PDB:1DO9"
FT   HELIX           86..88
FT                   /evidence="ECO:0007829|PDB:1DO9"
FT   TURN            89..91
FT                   /evidence="ECO:0007829|PDB:1DO9"
SQ   SEQUENCE   134 AA;  15349 MW;  B748AE9D32FA5E46 CRC64;
     MAAQSDKDVK YYTLEEIKKH NHSKSTWLIL HHKVYDLTKF LEEHPGGEEV LREQAGGDAT
     ENFEDVGHST DARELSKTFI IGELHPDDRS KLSKPMETLI TTVDSNSSWW TNWVIPAISA
     LIVALMYRLY MADD
//