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C4A complement C4A (Chido/Rodgers blood group) [ Homo sapiens (human) ]

Gene ID: 720, updated on 13-Apr-2024

Summary

Official Symbol
C4Aprovided by HGNC
Official Full Name
complement C4A (Chido/Rodgers blood group)provided by HGNC
Primary source
HGNC:HGNC:1323
See related
Ensembl:ENSG00000244731 MIM:120810; AllianceGenome:HGNC:1323
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
C4; RG; C4S; CO4; C4A2; C4A3; C4A4; C4A6; C4AD; CPAMD2
Summary
This gene encodes the acidic form of complement factor 4, 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 is cleaved to release C4 anaphylatoxin, an antimicrobial peptide and a mediator of local inflammation. Deficiency of this protein is associated with systemic lupus erythematosus and type I diabetes mellitus. 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. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Nov 2014]
Expression
Biased expression in liver (RPKM 487.9), adrenal (RPKM 99.6) and 7 other tissues See more
Orthologs
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Genomic context

See C4A in Genome Data Viewer
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 (31982057..32002681)
RS_2023_10 current T2T-CHM13v2.0 (GCF_009914755.1) 6 NC_060930.1 (31835263..31855887)
105.20220307 previous assembly GRCh37.p13 (GCF_000001405.25) 6 NC_000006.11 (31949834..31970458)

Chromosome 6 - NC_000006.12Genomic Context describing neighboring genes Neighboring gene CDK7 strongly-dependent group 2 enhancer GRCh37_chr6:31929542-31930741 Neighboring gene SKI2 subunit of superkiller complex Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr6:31939702-31940412 Neighboring gene serine/threonine kinase 19 Neighboring gene decapping exoribonuclease Neighboring gene CYP21A1P recombination region Neighboring gene cytochrome P450 family 21 subfamily A member 1, pseudogene Neighboring gene tenascin XA (pseudogene) recombination region Neighboring gene tenascin XA (pseudogene) Neighboring gene serine/threonine kinase 19B (pseudogene)

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
Blood group, Chido/Rodgers system
MedGen: C1292315 OMIM: 614374 GeneReviews: Not available
Compare labs
Decreased circulating complement C4a concentration
MedGen: C3280642 OMIM: 614380 GeneReviews: Not available
Compare labs

EBI GWAS Catalog

Description
Genome-wide association study for serum complement C3 and C4 levels in healthy Chinese subjects.
EBI GWAS Catalog
Identification of 23 new prostate cancer susceptibility loci using the iCOGS custom genotyping array.
EBI GWAS Catalog

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 complement component C1q complex 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 inflammatory response IEA
Inferred from Electronic Annotation
more info
 
involved_in innate immune response IEA
Inferred from Electronic Annotation
more info
 
involved_in positive regulation of apoptotic cell clearance IGI
Inferred from Genetic Interaction
more info
PubMed 

General protein information

Preferred Names
complement C4-A
Names
C3 and PZP-like alpha-2-macroglobulin domain-containing protein 2
C4A anaphylatoxin
MHC class III region complement
Rodgers form of C4
acidic C4
acidic complement C4
complement C4A (Rodgers blood group)
complement component 4A (Rodgers blood group)

NCBI Reference Sequences (RefSeq)

NEW Try the new Transcript table

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_011638.1 RefSeqGene

    Range
    5001..25624
    Download
    GenBank, FASTA, Sequence Viewer (Graphics), LRG_137

mRNA and Protein(s)

  1. NM_001252204.2NP_001239133.1  complement C4-A isoform 2 preproprotein

    See identical proteins and their annotated locations for NP_001239133.1

    Status: REVIEWED

    Description
    Transcript Variant: This variant (2) lacks an alternate in-frame segment compared to variant 1. The resulting isoform (2) has the same N- and C-termini but is shorter compared to isoform 1.
    Source sequence(s)
    AL645922, BC146673, DA304049, K02403
    Consensus CDS
    CCDS59005.1
    UniProtKB/TrEMBL
    A0A140TA32, A0A140TA44
    Related
    ENSP00000420212.1, ENST00000498271.1
    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:15421696
    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:14621524
    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
  2. NM_007293.3NP_009224.2  complement C4-A isoform 1 preproprotein

    See identical proteins and their annotated locations for NP_009224.2

    Status: REVIEWED

    Description
    Transcript Variant: This variant (1) represents the longer transcript and encodes the longer isoform (1).
    Source sequence(s)
    AL645922, BC016933, BC146673, DA304049, K02403
    Consensus CDS
    CCDS47404.1
    UniProtKB/Swiss-Prot
    A6H8M8, A6NHJ5, A7E2V2, B0QZR6, B0V2C8, B2RUT6, B7ZVZ6, P01028, P0C0L4, P78445, Q13160, Q13906, Q14033, Q14835, Q4LE82, Q5JNX2, Q5JQM8, Q6P4R1, Q6U2E5, Q6U2E8, Q6U2F0, Q6U2F3, Q6U2F4, Q6U2F6, Q6U2F8, Q6U2G0, Q96EG2, Q96SA8, Q9NPK5, Q9UIP5
    UniProtKB/TrEMBL
    A0A0G2JPR0
    Related
    ENSP00000396688.2, ENST00000428956.7
    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: 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
    31982057..32002681
    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
    3229830..3250455
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

Reference GRCh38.p14 ALT_REF_LOCI_6

Genomic

  1. NT_167248.2 Reference GRCh38.p14 ALT_REF_LOCI_6

    Range
    3238028..3258653
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

Alternate T2T-CHM13v2.0

Genomic

  1. NC_060930.1 Alternate T2T-CHM13v2.0

    Range
    31835263..31855887
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)