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

Gene ID: 721, updated on 20-Apr-2024

Summary

Official Symbol
C4Bprovided by HGNC
Official Full Name
complement C4B (Chido/Rodgers blood group)provided by HGNC
Primary source
HGNC:HGNC:1324
See related
Ensembl:ENSG00000224389 MIM:120820; AllianceGenome:HGNC:1324
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
Orthologs
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Genomic context

Location:
6p21.33
Exon count:
41
Annotation release Status Assembly Chr Location
RS_2023_10 current GRCh38.p14 (GCF_000001405.40) 6 NC_000006.12 (32014795..32035418)
RS_2023_10 current T2T-CHM13v2.0 (GCF_009914755.1) 6 NC_060930.1 (31868001..31888625)
105.20220307 previous assembly GRCh37.p13 (GCF_000001405.25) 6 NC_000006.11 (31982572..32003195)

Chromosome 6 - NC_000006.12Genomic Context describing neighboring genes Neighboring gene CYP21A1P recombination region 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 ReSE screen-validated silencer GRCh37_chr6:32013699-32013950 Neighboring gene P300/CBP strongly-dependent group 1 enhancer GRCh37_chr6:32014364-32015563 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr6:32015753-32016386 Neighboring gene tenascin XB Neighboring gene H3K4me1 hESC enhancer GRCh37_chr6:32038327-32039327 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr6:32040222-32041078 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr6:32041114-32041614 Neighboring gene RNA, 5S ribosomal pseudogene 206

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

EBI GWAS Catalog

Description
Identification of 23 new prostate cancer susceptibility loci using the iCOGS custom genotyping array.
EBI GWAS Catalog

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

Clone Names

  • FLJ60561, MGC164979

Gene Ontology Provided by GOA

Function Evidence Code Pubs
enables carbohydrate binding IDA
Inferred from Direct Assay
more info
PubMed 
enables complement binding IDA
Inferred from Direct Assay
more info
PubMed 
enables endopeptidase inhibitor activity IEA
Inferred from Electronic Annotation
more info
 
Process Evidence Code Pubs
involved_in complement activation IBA
Inferred from Biological aspect of Ancestor
more info
 
involved_in complement activation IGI
Inferred from Genetic Interaction
more info
PubMed 
involved_in complement activation, classical pathway IEA
Inferred from Electronic Annotation
more info
 
involved_in detection of molecule of bacterial origin IDA
Inferred from Direct Assay
more info
PubMed 
involved_in inflammatory response IEA
Inferred from Electronic Annotation
more info
 
involved_in innate immune response IEA
Inferred from Electronic Annotation
more info
 
involved_in opsonization TAS
Traceable Author Statement
more info
PubMed 
involved_in positive regulation of apoptotic cell clearance IGI
Inferred from Genetic Interaction
more info
PubMed 
Component Evidence Code Pubs
located_in axon IEA
Inferred from Electronic Annotation
more info
 
located_in blood microparticle HDA PubMed 
located_in dendrite IEA
Inferred from Electronic Annotation
more info
 
located_in extracellular exosome HDA PubMed 
located_in extracellular region TAS
Traceable Author Statement
more info
 
located_in extracellular space HDA PubMed 
is_active_in extracellular space IBA
Inferred from Biological aspect of Ancestor
more info
 
located_in extracellular space IDA
Inferred from Direct Assay
more info
PubMed 
located_in plasma membrane TAS
Traceable Author Statement
more info
 
located_in symbiont cell surface IDA
Inferred from Direct Assay
more info
PubMed 
located_in 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 C4B (Chido blood group)
complement C4B1a
complement component 4B (Chido blood group)

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_011639.1 RefSeqGene

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

mRNA and Protein(s)

  1. NM_001002029.4 → NP_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
    A2BHY4, P0C0L5, Q6U2E9, Q6U2G1, Q6U2I5, Q6U2L1, Q6U2L7, Q6U2L9, Q6U2M5, Q6VCV8, Q96SA7
    UniProtKB/TrEMBL
    A0A0G2JPR0
    Related
    ENSP00000415941.2, ENST00000435363.7
    Conserved Domains (8) summary
    cd00017
    Location:686 → 750
    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:996 → 1315
    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:1588 → 1742
    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:782 → 869
    A2M; Alpha-2-macroglobulin family
    pfam01835
    Location:141 → 233
    A2M_N; MG2 domain
    pfam07677
    Location:1481 → 1570
    A2M_recep; A-macroglobulin receptor
    pfam07678
    Location:1051 → 1317
    A2M_comp; A-macroglobulin complement component
    pfam07703
    Location:478 → 610
    A2M_N_2; Alpha-2-macroglobulin family N-terminal region

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_000006.12 Reference GRCh38.p14 Primary Assembly

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

Reference GRCh38.p14 ALT_REF_LOCI_2

Genomic

  1. NT_113891.3 Reference GRCh38.p14 ALT_REF_LOCI_2

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

Reference GRCh38.p14 ALT_REF_LOCI_3

Genomic

  1. NT_167245.2 Reference GRCh38.p14 ALT_REF_LOCI_3

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

Reference GRCh38.p14 ALT_REF_LOCI_7

Genomic

  1. NT_167249.2 Reference GRCh38.p14 ALT_REF_LOCI_7

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

Alternate T2T-CHM13v2.0

Genomic

  1. NC_060930.1 Alternate T2T-CHM13v2.0

    Range
    31868001..31888625
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)