Reviewed, UniProtKB/Swiss-Prot P04166 (CYB5B_RAT)

Names and origin

Protein names

Recommended name:
    Cytochrome b5 type B
Alternative name(s):
    Cytochrome b5 outer mitochondrial membrane isoform

Gene names

Name:	Cyb5b
Synonyms:	Cyb5m, Omb5

Organism

Rattus norvegicus (Rat)

Taxonomic identifier

10116 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Glires › Rodentia › Sciurognathi › Muroidea › Muridae › Murinae › Rattus

Protein attributes

Sequence length	146 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Cytochrome b5 is a membrane bound hemoprotein which function as an electron carrier for several membrane bound oxygenases.
Subunit structure	Component of a complex composed of cytochrome b5, NADH-cytochrome b5 reductase (CYB5R3) and MOSC2 By similarity.
Subcellular location	Mitochondrion outer membrane.
Sequence similarities	Belongs to the cytochrome b5 family. Contains 1 cytochrome b5 heme-binding domain.

Ontologies

Keywords
Biological process	Electron transport Transport
Cellular component	Membrane Mitochondrion Mitochondrion outer membrane
Domain	Transmembrane
Ligand	Heme Iron Metal-binding
PTM	Acetylation
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Biological process	electron transport chain Inferred from electronic annotation. Source: UniProtKB-KW transport Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW microsome Inferred from direct assay. Source: RGD mitochondrial outer membrane Inferred from direct assay. Source: RGD
Molecular function	electron transporter, transferring electrons within CoQH2-cytochrome c reductase complex activity Traceable author statement. Source: RGD enzyme activator activity Inferred from direct assay. Source: RGD heme binding Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Propeptide

1 – 11

11

PRO_0000006477

Chain

12 – 146

135

Cytochrome b5 type B

PRO_0000006478

Regions

Transmembrane

119 – 136

18

Potential

Domain

20 – 96

77

Cytochrome b5 heme-binding

Sites

Metal binding

55

1

Iron (heme axial ligand)

Metal binding

79

1

Iron (heme axial ligand)

Amino acid modifications

Modified residue

30

1

N6-acetyllysine By similarity

Experimental info

Sequence conflict

12

1

N → D AA sequence Ref.3

Secondary structure

1

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

146

Helix Strand Turn

Details...

Helix

25 – 28

4

Beta strand

36 – 41

6

Beta strand

44 – 47

4

Turn

49 – 54

6

Helix

60 – 64

5

Turn

65 – 67

3

Helix

71 – 76

6

Helix

81 – 87

7

Turn

88 – 90

3

Beta strand

91 – 95

5

Helix

97 – 99

3

Sequences

	Sequence		Length	Mass (Da)
	P04166-1 [UniParc]. Last modified January 11, 2001. Version 2. Checksum: 1CA90DD3C81C412E	FASTA	146	16,265
	10 20 30 40 50 60 MATPEASGSG RNGQGSDPAV TYYRLEEVAK RNTAEETWMV IHGRVYDITR FLSEHPGGEE 70 80 90 100 110 120 VLLEQAGADA TESFEDVGHS PDAREMLKQY YIGDVHPNDL KPKDGDKDPS KNNSCQSSWA 130 140 YWIVPIVGAI LIGFLYRHFW ADSKSS

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Charged amino acids at the carboxy-terminal portions determine intracellular locations of two isoforms of cytochrome b5." Kuroda R., Ikenoue T., Honsho M., Tujimoto S., Miroma J., Ito A. Submitted (APR-1997) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[2]	"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)." The MGC Project Team Genome Res. 14:2121-2127(2004) [PubMed: 15489334] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Tissue: Heart.
[3]	"Two homologous cytochromes b5 in a single cell." Lederer F., Ghrir R., Guiard B., Cortial S., Ito A. Eur. J. Biochem. 132:95-102(1983) [PubMed: 6840088] [Abstract] Cited for: PROTEIN SEQUENCE OF 12-103.
[4]	"13C NMR spectroscopic and X-ray crystallographic study of the role played by mitochondrial cytochrome b5 heme propionates in the electrostatic binding to cytochrome c." Rodriguez-Maranon M.J., Qiu F., Stark R.E., White S.P., Zhang X., Foundling S.I., Rodriguez V., Schilling C.L. III, Bunce R.A., Rivera M. Biochemistry 35:16378-16390(1996) [PubMed: 8973214] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.7 ANGSTROMS).
[5]	"The reduction potential of cytochrome b5 is modulated by its exposed heme edge." Rivera M., Seetharaman R., Girdhar D., Wirtz M., Zhang X., Wang X., White S. Biochemistry 37:1485-1494(1998) [PubMed: 9484218] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS).
[6]	"Modulation of redox potential in electron transfer proteins: effects of complex formation on the active site microenvironment of cytochrome b5." Wirtz M., Oganesyan V., Zhang X., Studer J., Rivera M. Faraday Discuss. 116:221-234(2000) [PubMed: 11197480] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS) OF 17-102.
[7]	"Probing the differences between rat liver outer mitochondrial membrane cytochrome b5 and microsomal cytochromes b5." Altuve A., Silchenko S., Lee K.-H., Kuczera K., Terzyan S., Zhang X., Benson D.R., Rivera M. Biochemistry 40:9469-9483(2001) [PubMed: 11583146] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS) OF 17-103.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBLGenBankDDBJ

Y12517 mRNA. Translation: CAA73117.1.
BC072535 mRNA. Translation: AAH72535.1.

IPI

IPI00193233.

RefSeq

NP_085075.1.

UniGene

Rn.10249

3D structure databases

PDBPDBe

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1AWP	X-ray	2.00	A/B	13-103	[»]
1B5M	X-ray	2.70	A	19-102	[»]
1EUE	X-ray	1.80	A/B	17-102	[»]
1ICC	X-ray	2.00	A/B/C/D	17-103	[»]
1LJ0	X-ray	2.00	A/B/C/D	12-103	[»]
2I89	X-ray	2.10	A/B/C/D	12-103	[»]

ModBase

Search...

Protein-protein interaction databases

STRING

P04166.

Proteomic databases

PRIDE

P04166.

Genome annotation databases

Ensembl

ENSRNOT00000014966; ENSRNOP00000014966; ENSRNOG00000011142; Rattus norvegicus. [Genome view]
ENSRNOT00000015006; ENSRNOP00000015006; ENSRNOG00000011142; Rattus norvegicus. [Genome view]

GeneID

80773.

KEGG

rno:80773.

UCSC

NM_030586. rat.

Organism-specific databases

CTD

80773.

RGD

621551. Cyb5b.

Phylogenomic databases

HOVERGEN

P04166.

Gene expression databases

ArrayExpress

P04166.

Genevestigator

P04166.

GermOnline

ENSRNOG00000011142. Rattus norvegicus.

Family and domain databases

InterPro

IPR001199. Cyt_B5.
IPR018506. Cyt_B5_heme-BS.
[Graphical view]

Gene3D

G3DSA:3.10.120.10. Cyt_B5. 1 hit.

Pfam

PF00173. Cyt-b5. 1 hit.
[Graphical view]

PRINTS

PR00363. CYTOCHROMEB5.

ProDom

PD000612. Cyt_B5. 1 hit.
[Graphical view] [Entries sharing at least one domain]

PROSITE

PS00191. CYTOCHROME_B5_1. 1 hit.
PS50255. CYTOCHROME_B5_2. 1 hit.
[Graphical view]

ProtoNet

Search...

Other Resources

NextBio

614866.

Entry information

Entry name

CYB5B_RAT

Accession

Primary (citable) accession number: P04166
Secondary accession number(s): Q9QWG1

Entry history

Integrated into UniProtKB/Swiss-Prot:	March 20, 1987
Last sequence update:	January 11, 2001
Last modified:	October 13, 2009
This is version 93 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)