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CYB5R4 cytochrome b5 reductase 4 [ Homo sapiens (human) ]

Gene ID: 51167, updated on 9-Jun-2025
Official Symbol
CYB5R4provided by HGNC
Official Full Name
cytochrome b5 reductase 4provided by HGNC
Primary source
HGNC:HGNC:20147
See related
Ensembl:ENSG00000065615 MIM:608343; AllianceGenome:HGNC:20147
Gene type
protein coding
RefSeq status
VALIDATED
Organism
Homo sapiens
Lineage
Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo
Also known as
NCB5OR; cb5/cb5R; dJ676J13.1
Summary
NCB5OR is a flavohemoprotein that contains functional domains found in both cytochrome b5 (CYB5A; MIM 613218) and CYB5 reductase (CYB5R3; MIM 613213) (Zhu et al., 1999 [PubMed 10611283]).[supplied by OMIM, Jan 2010]
Expression
Broad expression in testis (RPKM 17.2), appendix (RPKM 16.0) and 24 other tissues See more
Orthologs
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See CYB5R4 in Genome Data Viewer
Location:
6q14.2
Exon count:
16
Annotation release Status Assembly Chr Location
RS_2024_08 current GRCh38.p14 (GCF_000001405.40) 6 NC_000006.12 (83859689..83967423)
RS_2024_08 current T2T-CHM13v2.0 (GCF_009914755.1) 6 NC_060930.1 (85082972..85190710)
RS_2024_09 previous assembly GRCh37.p13 (GCF_000001405.25) 6 NC_000006.11 (84569408..84677142)

Chromosome 6 - NC_000006.12Genomic Context describing neighboring genes Neighboring gene uncharacterized LOC105377879 Neighboring gene MPRA-validated peak5930 silencer Neighboring gene RIPPLY2-CYB5R4 readthrough Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 17361 Neighboring gene Sharpr-MPRA regulatory region 3398 Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 17362 Neighboring gene ripply transcriptional repressor 2 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr6:84615227-84615728 Neighboring gene CRISPRi-validated cis-regulatory element chr6.3721 Neighboring gene CDK7 strongly-dependent group 2 enhancer GRCh37_chr6:84686166-84687365 Neighboring gene MPRA-validated peak5932 silencer Neighboring gene long intergenic non-protein coding RNA 2857 Neighboring gene VISTA enhancer hs2063 Neighboring gene H3K27ac hESC enhancer GRCh37_chr6:84782671-84783171 Neighboring gene melanocortin 2 receptor accessory protein 2 Neighboring gene MPRA-validated peak5934 silencer Neighboring gene centrosomal protein 162

  • Project title: Tissue-specific circular RNA induction during human fetal development
  • Description: 35 human fetal samples from 6 tissues (3 - 7 replicates per tissue) collected between 10 and 20 weeks gestational time were sequenced using Illumina TruSeq Stranded Total RNA
  • BioProject: PRJNA270632
  • Publication: PMID 26076956
  • Analysis date: Mon Apr 2 22:54:59 2018

GeneRIFs: Gene References Into Functions

What's a GeneRIF?
Products Interactant Other Gene Complex Source Pubs Description

Markers

Readthrough RIPPLY2-CYB5R4

Readthrough gene: RIPPLY2-CYB5R4, Included gene: RIPPLY2

Gene Ontology Provided by GOA

Process Evidence Code Pubs
involved_in bicarbonate transport TAS
Traceable Author Statement
more info
 
acts_upstream_of_or_within cell development IEA
Inferred from Electronic Annotation
more info
 
involved_in cell development ISS
Inferred from Sequence or Structural Similarity
more info
 
involved_in detection of oxygen NAS
Non-traceable Author Statement
more info
PubMed 
acts_upstream_of_or_within glucose homeostasis IEA
Inferred from Electronic Annotation
more info
 
involved_in glucose homeostasis ISS
Inferred from Sequence or Structural Similarity
more info
 
acts_upstream_of_or_within insulin secretion IEA
Inferred from Electronic Annotation
more info
 
involved_in insulin secretion ISS
Inferred from Sequence or Structural Similarity
more info
 
involved_in reactive oxygen species metabolic process IDA
Inferred from Direct Assay
more info
PubMed 
acts_upstream_of_or_within response to antibiotic IEA
Inferred from Electronic Annotation
more info
 
involved_in response to antibiotic ISS
Inferred from Sequence or Structural Similarity
more info
 
involved_in superoxide metabolic process IBA
Inferred from Biological aspect of Ancestor
more info
 
involved_in superoxide metabolic process IDA
Inferred from Direct Assay
more info
PubMed 
Component Evidence Code Pubs
is_active_in cytoplasm IBA
Inferred from Biological aspect of Ancestor
more info
 
is_active_in endoplasmic reticulum IBA
Inferred from Biological aspect of Ancestor
more info
 
located_in endoplasmic reticulum IDA
Inferred from Direct Assay
more info
PubMed 
located_in endoplasmic reticulum IEA
Inferred from Electronic Annotation
more info
 
located_in endoplasmic reticulum membrane TAS
Traceable Author Statement
more info
 
located_in perinuclear region of cytoplasm IDA
Inferred from Direct Assay
more info
PubMed 
Preferred Names
cytochrome b5 reductase 4
Names
N-terminal cytochrome b5 and cytochrome b5 oxidoreductase domain-containing protein
NADPH cytochrome B5 oxidoreductase
cytochrome b-type NAD(P)H oxidoreductase
flavohemoprotein b5+b5R
flavohemoprotein b5/b5R
NP_057314.2

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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.

mRNA and Protein(s)

  1. NM_016230.4NP_057314.2  cytochrome b5 reductase 4

    See identical proteins and their annotated locations for NP_057314.2

    Status: VALIDATED

    Source sequence(s)
    AL034347, BC025380, BC029339, DA274558
    Consensus CDS
    CCDS5000.2
    UniProtKB/Swiss-Prot
    B1AEM2, Q5TGI9, Q7L1T6, Q9NUE4, Q9UHI9
    Related
    ENSP00000358695.3, ENST00000369681.10
    Conserved Domains (3) summary
    cd06183
    Location:278519
    cyt_b5_reduct_like; Cytochrome b5 reductase catalyzes the reduction of 2 molecules of cytochrome b5 using NADH as an electron donor. Like ferredoxin reductases, these proteins have an N-terminal FAD binding subdomain and a C-terminal NADH binding subdomain, separated by a ...
    cd06490
    Location:170256
    p23_NCB5OR; p23_like domain found in NAD(P)H cytochrome b5 (NCB5) oxidoreductase (OR) and similar proteins. NCB5OR is widely expressed in human organs and tissues and is localized in the ER (endoplasmic reticulum). It appears to play a critical role in maintaining ...
    pfam00173
    Location:58130
    Cyt-b5; Cytochrome b5-like Heme/Steroid binding domain

RefSeqs of Annotated Genomes: GCF_000001405.40-RS_2024_08

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

Reference GRCh38.p14 Primary Assembly

Genomic

  1. NC_000006.12 Reference GRCh38.p14 Primary Assembly

    Range
    83859689..83967423
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

Alternate T2T-CHM13v2.0

Genomic

  1. NC_060930.1 Alternate T2T-CHM13v2.0

    Range
    85082972..85190710
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)