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C4B complement C4B (Chido blood group) [ Homo sapiens (human) ]

Gene ID: 721, updated on 25-Oct-2020

Summary

Official Symbol
C4Bprovided by HGNC
Official Full Name
complement C4B (Chido blood group)provided by HGNC
Primary source
HGNC:HGNC:1324
See related
Ensembl:ENSG00000224389 MIM:120820
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
CH; C4F; CO4; C4B1; C4B2; C4B3; C4B5; C4BD; C4B12; C4B_2; CPAMD3
Summary
This gene encodes the basic form of complement factor 4, and together with the C4A gene, is part of the classical activation pathway. The protein is expressed as a single chain precursor which is proteolytically cleaved into a trimer of alpha, beta, and gamma chains prior to secretion. The trimer provides a surface for interaction between the antigen-antibody complex and other complement components. The alpha chain may be cleaved to release C4 anaphylatoxin, a mediator of local inflammation. Deficiency of this protein is associated with systemic lupus erythematosus. This gene localizes to the major histocompatibility complex (MHC) class III region on chromosome 6. Varying haplotypes of this gene cluster exist, such that individuals may have 1, 2, or 3 copies of this gene. In addition, this gene exists as a long form and a short form due to the presence or absence of a 6.4 kb endogenous HERV-K retrovirus in intron 9. [provided by RefSeq, May 2020]
Expression
Biased expression in liver (RPKM 500.9), adrenal (RPKM 103.5) and 6 other tissues See more

Genomic context

See C4B in Genome Data Viewer
Location:
6p21.33
Exon count:
41
Annotation release Status Assembly Chr Location
109.20200815 current GRCh38.p13 (GCF_000001405.39) 6 NC_000006.12 (32014795..32035418)
105 previous assembly GRCh37.p13 (GCF_000001405.25) 6 NC_000006.11 (31982572..32003195)

Chromosome 6 - NC_000006.12Genomic Context describing neighboring genes Neighboring gene tenascin XA (pseudogene) recombination region Neighboring gene cytochrome P450 family 21 subfamily A member 1, pseudogene Neighboring gene tenascin XA (pseudogene) Neighboring gene serine/threonine kinase 19B (pseudogene) Neighboring gene CYP21A2 5' regulatory region Neighboring gene CYP21A2 recombination region Neighboring gene tenascin XB recombination region Neighboring gene cytochrome P450 family 21 subfamily A member 2 Neighboring gene tenascin XB

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?

Phenotypes

Associated conditions

Description Tests
Complement component 4b deficiency
MedGen: C3280641 OMIM: 614379 GeneReviews: Not available
Compare labs
Identification of 23 new prostate cancer susceptibility loci using the iCOGS custom genotyping array.
GeneReviews: Not available

HIV-1 interactions

Protein interactions

Protein Gene Interaction Pubs
Envelope surface glycoprotein gp120 env Preincubation of HIV-1 gp41 with either factor H or properdin, and of HIV-1 gp120 with C3b or C4b affect the interaction between HIV-1 gp41 and gp120 PubMed
env A synthetic peptide covering positions 233-251 of the HIV-1 gp120 protein binds to complement proteins C3, C4, C5, C9, and properdin PubMed
env Complement proteins C4, C3d, C5b-9, and properdin bind to HIV-1 gp120-coated CD4+ T cells of healthy individuals when incubated in autologous serum PubMed
env Amino acid residues 410-449 of HIV-1 gp120 are involved in its binding to C4b PubMed

Go to the HIV-1, Human Interaction Database

Pathways from PubChem

Interactions

Products Interactant Other Gene Complex Source Pubs Description

General gene information

Markers

Homology

Clone Names

  • FLJ60561, MGC164979

Gene Ontology Provided by GOA

Function Evidence Code Pubs
carbohydrate binding IDA
Inferred from Direct Assay
more info
PubMed 
complement binding IDA
Inferred from Direct Assay
more info
PubMed 
endopeptidase inhibitor activity IEA
Inferred from Electronic Annotation
more info
 
Process Evidence Code Pubs
complement activation IBA
Inferred from Biological aspect of Ancestor
more info
PubMed 
complement activation IGI
Inferred from Genetic Interaction
more info
PubMed 
complement activation TAS
Traceable Author Statement
more info
 
complement activation, classical pathway IEA
Inferred from Electronic Annotation
more info
 
detection of molecule of bacterial origin IDA
Inferred from Direct Assay
more info
PubMed 
inflammatory response IEA
Inferred from Electronic Annotation
more info
 
innate immune response IEA
Inferred from Electronic Annotation
more info
 
negative regulation of endopeptidase activity IEA
Inferred from Electronic Annotation
more info
 
opsonization TAS
Traceable Author Statement
more info
PubMed 
positive regulation of apoptotic cell clearance IGI
Inferred from Genetic Interaction
more info
PubMed 
regulation of complement activation TAS
Traceable Author Statement
more info
 
Component Evidence Code Pubs
axon IEA
Inferred from Electronic Annotation
more info
 
blood microparticle HDA PubMed 
dendrite IEA
Inferred from Electronic Annotation
more info
 
extracellular exosome HDA PubMed 
extracellular region TAS
Traceable Author Statement
more info
 
extracellular space HDA PubMed 
extracellular space IBA
Inferred from Biological aspect of Ancestor
more info
PubMed 
extracellular space IDA
Inferred from Direct Assay
more info
PubMed 
other organism cell IDA
Inferred from Direct Assay
more info
PubMed 
plasma membrane TAS
Traceable Author Statement
more info
 
synapse IEA
Inferred from Electronic Annotation
more info
 

General protein information

Preferred Names
complement C4-B
Names
C3 and PZP-like alpha-2-macroglobulin domain-containing protein 3
Chido form of C4
basic complement C4
complement C4B1a
complement component 4B (Chido blood group)

NCBI Reference Sequences (RefSeq)

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_011639.1 RefSeqGene

    Range
    5002..25625
    Download
    GenBank, FASTA, Sequence Viewer (Graphics), LRG_138

mRNA and Protein(s)

  1. NM_001002029.4NP_001002029.3  complement C4-B preproprotein

    See identical proteins and their annotated locations for NP_001002029.3

    Status: REVIEWED

    Source sequence(s)
    AL645922
    Consensus CDS
    CCDS47405.1
    UniProtKB/Swiss-Prot
    P0C0L4, P0C0L5
    Related
    ENSP00000415941.2, ENST00000435363.7
    Conserved Domains (8) summary
    cd00017
    Location:686750
    ANATO; Anaphylatoxin homologous domain; C3a, C4a and C5a anaphylatoxins are protein fragments generated enzymatically in serum during activation of complement molecules C3, C4, and C5. They induce smooth muscle contraction. These fragments are homologous to ...
    cd02896
    Location:9961315
    complement_C3_C4_C5; Proteins similar to C3, C4 and C5 of vertebrate complement. The vertebrate complement system, comprised of a large number of distinct plasma proteins, is an effector of both the acquired and innate immune systems. The point of convergence of the ...
    cd03584
    Location:15881742
    NTR_complement_C4; NTR/C345C domain, complement C4 subfamily; The NTR domain found in complement C4 is also known as the C345C domain because it occurs at the C-terminus of complement C3, C4 and C5. Complement C4 is a key player in the activation of the component classical ...
    pfam00207
    Location:782869
    A2M; Alpha-2-macroglobulin family
    pfam01835
    Location:141233
    A2M_N; MG2 domain
    pfam07677
    Location:14811570
    A2M_recep; A-macroglobulin receptor
    pfam07678
    Location:10511317
    A2M_comp; A-macroglobulin complement component
    pfam07703
    Location:478610
    A2M_N_2; Alpha-2-macroglobulin family N-terminal region

RefSeqs of Annotated Genomes: Homo sapiens Updated Annotation Release 109.20200815

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

Reference GRCh38.p13 Primary Assembly

Genomic

  1. NC_000006.12 Reference GRCh38.p13 Primary Assembly

    Range
    32014795..32035418
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

Reference GRCh38.p13 ALT_REF_LOCI_2

Genomic

  1. NT_113891.3 Reference GRCh38.p13 ALT_REF_LOCI_2

    Range
    3459484..3473740
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

Reference GRCh38.p13 ALT_REF_LOCI_3

Genomic

  1. NT_167245.2 Reference GRCh38.p13 ALT_REF_LOCI_3

    Range
    3262570..3276826
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

Reference GRCh38.p13 ALT_REF_LOCI_7

Genomic

  1. NT_167249.2 Reference GRCh38.p13 ALT_REF_LOCI_7

    Range
    3315984..3336608
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)
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