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CYB5A cytochrome b5 type A [ Homo sapiens (human) ]

Gene ID: 1528, updated on 7-Jan-2024

Summary

Official Symbol
CYB5Aprovided by HGNC
Official Full Name
cytochrome b5 type Aprovided by HGNC
Primary source
HGNC:HGNC:2570
See related
Ensembl:ENSG00000166347 MIM:613218; AllianceGenome:HGNC:2570
Gene type
protein coding
RefSeq status
REVIEWED
Organism
Homo sapiens
Lineage
Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo
Also known as
CYB5; MCB5; METAG
Summary
The protein encoded by this gene is a membrane-bound cytochrome that reduces ferric hemoglobin (methemoglobin) to ferrous hemoglobin, which is required for stearyl-CoA-desaturase activity. Defects in this gene are a cause of type IV hereditary methemoglobinemia. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2010]
Expression
Broad expression in liver (RPKM 226.1), kidney (RPKM 141.0) and 16 other tissues See more
Orthologs
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Genomic context

See CYB5A in Genome Data Viewer
Location:
18q22.3
Exon count:
6
Annotation release Status Assembly Chr Location
RS_2023_10 current GRCh38.p14 (GCF_000001405.40) 18 NC_000018.10 (74250846..74291963, complement)
RS_2023_10 current T2T-CHM13v2.0 (GCF_009914755.1) 18 NC_060942.1 (74478400..74519513, complement)
105.20220307 previous assembly GRCh37.p13 (GCF_000001405.25) 18 NC_000018.9 (71918081..71959198, complement)

Chromosome 18 - NC_000018.10Genomic Context describing neighboring genes Neighboring gene ATAC-STARR-seq lymphoblastoid active region 13491 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 13492 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 13493 Neighboring gene BRD4-independent group 4 enhancer GRCh37_chr18:71817752-71818951 Neighboring gene BRD4-independent group 4 enhancer GRCh37_chr18:71822138-71823337 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 13494 Neighboring gene Neanderthal introgressed variant-containing enhancer experimental_50247 Neighboring gene translocase of inner mitochondrial membrane 21 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr18:71864836-71865492 Neighboring gene RNA, 7SL, cytoplasmic 551, pseudogene Neighboring gene H3K4me1 hESC enhancer GRCh37_chr18:71904867-71905366 Neighboring gene Sharpr-MPRA regulatory region 12176 Neighboring gene NANOG-H3K27ac hESC enhancer GRCh37_chr18:71917515-71918450 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr18:71935092-71935632 Neighboring gene Neanderthal introgressed variant-containing enhancer experimental_50263 Neighboring gene Neanderthal introgressed variant-containing enhancer experimental_50279 Neighboring gene OCT4-NANOG-H3K27ac-H3K4me1 hESC enhancer GRCh37_chr18:71948314-71948841 Neighboring gene Neanderthal introgressed variant-containing enhancer experimental_50293 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr18:71957777-71958384 Neighboring gene Neanderthal introgressed variant-containing enhancer experimental_50301 Neighboring gene Neanderthal introgressed variant-containing enhancer experimental_50303 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 13495 Neighboring gene Neanderthal introgressed variant-containing enhancer experimental_50307 Neighboring gene MPRA-validated peak3184 silencer Neighboring gene Neanderthal introgressed variant-containing enhancer experimental_50330 Neighboring gene Neanderthal introgressed variant-containing enhancer experimental_50334 Neighboring gene Neanderthal introgressed variant-containing enhancer experimental_50341 Neighboring gene chromosome 18 open reading frame 63 Neighboring gene Neanderthal introgressed variant-containing enhancer experimental_50347 Neighboring gene Neanderthal introgressed variant-containing enhancers experimental_50353 and experimental_50354 Neighboring gene NANOG hESC enhancer GRCh37_chr18:72050693-72051551 Neighboring gene FAU pseudogene 1

Genomic regions, transcripts, and products

Expression

  • Project title: HPA RNA-seq normal tissues
  • Description: RNA-seq was performed of tissue samples from 95 human individuals representing 27 different tissues in order to determine tissue-specificity of all protein-coding genes
  • BioProject: PRJEB4337
  • Publication: PMID 24309898
  • Analysis date: Wed Apr 4 07:08:55 2018

Bibliography

GeneRIFs: Gene References Into Functions

What's a GeneRIF?

Pathways from PubChem

Interactions

Products Interactant Other Gene Complex Source Pubs Description

General gene information

Markers

Gene Ontology Provided by GOA

Function Evidence Code Pubs
enables cytochrome-c oxidase activity TAS
Traceable Author Statement
more info
PubMed 
enables enzyme binding IPI
Inferred from Physical Interaction
more info
PubMed 
enables heme binding IBA
Inferred from Biological aspect of Ancestor
more info
 
enables metal ion binding IEA
Inferred from Electronic Annotation
more info
 
enables protein binding IPI
Inferred from Physical Interaction
more info
PubMed 
Process Evidence Code Pubs
involved_in electron transport chain IEA
Inferred from Electronic Annotation
more info
 
involved_in proton transmembrane transport IEA
Inferred from Electronic Annotation
more info
 
Component Evidence Code Pubs
located_in cytosol IDA
Inferred from Direct Assay
more info
 
located_in cytosol TAS
Traceable Author Statement
more info
 
is_active_in endoplasmic reticulum membrane IBA
Inferred from Biological aspect of Ancestor
more info
 
is_active_in intracellular membrane-bounded organelle IBA
Inferred from Biological aspect of Ancestor
more info
 
located_in intracellular membrane-bounded organelle IDA
Inferred from Direct Assay
more info
 
located_in membrane HDA PubMed 
located_in membrane IDA
Inferred from Direct Assay
more info
PubMed 
is_active_in mitochondrial outer membrane IBA
Inferred from Biological aspect of Ancestor
more info
 
located_in mitochondrial outer membrane TAS
Traceable Author Statement
more info
 

General protein information

Preferred Names
cytochrome b5
Names
cytochrome b5 type A (microsomal)
epididymis secretory sperm binding protein
type 1 cyt-b5

NCBI Reference Sequences (RefSeq)

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RefSeqs maintained independently of Annotated Genomes

These reference sequences exist independently of genome builds. Explain

These reference sequences are curated independently of the genome annotation cycle, so their versions may not match the RefSeq versions in the current genome build. Identify version mismatches by comparing the version of the RefSeq in this section to the one reported in Genomic regions, transcripts, and products above.

Genomic

  1. NG_023211.2 RefSeqGene

    Range
    5000..46117
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

mRNA and Protein(s)

  1. NM_001190807.3NP_001177736.1  cytochrome b5 isoform 3

    Status: REVIEWED

    Description
    Transcript Variant: This variant (3) lacks an alternate in-frame exon in the 3' coding region, compared to variant 1. The resulting isoform (3) has the same N- and C-termini but is shorter compared to isoform 1.
    Source sequence(s)
    AC090398, BG196223, CA771478, CB112646
    Consensus CDS
    CCDS54188.1
    UniProtKB/Swiss-Prot
    P00167
    Related
    ENSP00000381011.4, ENST00000397914.4
    Conserved Domains (1) summary
    pfam00173
    Location:1385
    Cyt-b5; Cytochrome b5-like Heme/Steroid binding domain
  2. NM_001914.4NP_001905.1  cytochrome b5 isoform 2

    See identical proteins and their annotated locations for NP_001905.1

    Status: REVIEWED

    Description
    Transcript Variant: This variant (2) has an additional exon in the 3' coding region, which introduces a stop codon, as compared to variant 1. The encoded isoform (2) has a shorter and distinct C-terminus, as compared to isoform 1.
    Source sequence(s)
    AC090398, BG196223, CB112646, M60174
    Consensus CDS
    CCDS12005.1
    UniProtKB/Swiss-Prot
    P00167
    Related
    ENSP00000436461.2, ENST00000494131.6
    Conserved Domains (1) summary
    pfam00173
    Location:1385
    Cyt-b5; Cytochrome b5-like Heme/Steroid binding domain
  3. NM_148923.4NP_683725.1  cytochrome b5 isoform 1

    See identical proteins and their annotated locations for NP_683725.1

    Status: REVIEWED

    Description
    Transcript Variant: This variant (1) represents the longest transcript and encodes the longest isoform (1).
    Source sequence(s)
    AC090398, BC015182, BG196223, CB112646
    Consensus CDS
    CCDS12004.1
    UniProtKB/Swiss-Prot
    A8MV91, F8WEU4, P00167, Q6IB14
    UniProtKB/TrEMBL
    A0A384ME44
    Related
    ENSP00000341625.4, ENST00000340533.9
    Conserved Domains (1) summary
    pfam00173
    Location:1385
    Cyt-b5; Cytochrome b5-like Heme/Steroid binding domain

RefSeqs of Annotated Genomes: GCF_000001405.40-RS_2023_10

The following sections contain reference sequences that belong to a specific genome build. Explain

Reference GRCh38.p14 Primary Assembly

Genomic

  1. NC_000018.10 Reference GRCh38.p14 Primary Assembly

    Range
    74250846..74291963 complement
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

mRNA and Protein(s)

  1. XM_011525835.3XP_011524137.1  cytochrome b5 isoform X1

    See identical proteins and their annotated locations for XP_011524137.1

    UniProtKB/Swiss-Prot
    P00167
    Conserved Domains (1) summary
    pfam00173
    Location:1385
    Cyt-b5; Cytochrome b5-like Heme/Steroid binding domain

Alternate T2T-CHM13v2.0

Genomic

  1. NC_060942.1 Alternate T2T-CHM13v2.0

    Range
    74478400..74519513 complement
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

mRNA and Protein(s)

  1. XM_054318223.1XP_054174198.1  cytochrome b5 isoform X1