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C4B_2 complement component 4B (Chido/Rodgers blood group), copy 2 [ Homo sapiens (human) ]

Gene ID: 100293534, updated on 2-Nov-2024

Summary

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Official Symbol
C4B_2provided by HGNC
Official Full Name
complement component 4B (Chido/Rodgers blood group), copy 2provided by HGNC
Primary source
HGNC:HGNC:42398
See related
AllianceGenome:HGNC:42398
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
Summary
This gene encodes the basic 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 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. This GeneID and its associated RefSeq record represent a second copy of C4B found on ALT_REF_LOCI_7. [provided by RefSeq, Jul 2011]
Annotation information
Annotation category: only annotated on alternate loci in reference assembly
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Genomic context

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See C4B_2 in Genome Data Viewer
Location:
6p21.3 alternate reference locus
Exon count:
41
Annotation release Status Assembly Chr Location
RS_2024_08 current GRCh38.p14 (GCF_000001405.40) 6 (ALT_REF_LOCI_7) NT_167249.2 (3283246..3303870)
RS_2024_09 previous assembly GRCh37.p13 (GCF_000001405.25) 6 Unlocalized Scaffold (ALT_REF_LOCI_7) NT_167249.1 (3282544..3303168)

NT_167249.2Genomic 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 cytochrome P450 family 21 subfamily A member 1, pseudogene Neighboring gene tenascin XA (pseudogene) Neighboring gene serine/threonine kinase 19B (pseudogene)

Genomic regions, transcripts, and products

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Go to nucleotide: Graphics FASTA GenBank

Bibliography

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Related articles in PubMed

  1. A review of the Chido/Rodgers blood group. Mougey R. Immunohematology, 2010. PMID 20795316
  2. Low complement C4B gene copy number predicts short-term mortality after acute myocardial infarction. Blaskó B, et al. Int Immunol, 2008 Jan. PMID 18032375
  3. Genetic sophistication of human complement components C4A and C4B and RP-C4-CYP21-TNX (RCCX) modules in the major histocompatibility complex. Chung EK, et al. Am J Hum Genet, 2002 Oct. PMID 12226794, Free PMC Article
  4. Determining the one, two, three, or four long and short loci of human complement C4 in a major histocompatibility complex haplotype encoding C4A or C4B proteins. Chung EK, et al. Am J Hum Genet, 2002 Oct. PMID 12224044, Free PMC Article
  5. The structural basis of the multiple forms of human complement component C4. Belt KT, et al. Cell, 1984 Apr. PMID 6546707

See all (11) citations in PubMed

GeneRIFs: Gene References Into Functions

Variation

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See studies and variants in dbVar

See Variation Viewer (GRCh37.p13)

See Variation Viewer (GRCh38)

Genotypes

Pathways from PubChem

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Interactions

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Products Interactant Other Gene Complex Source Pubs Description

General gene information

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Markers

Homology

General protein information

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Preferred Names
complement C4-B-like
Names
complement component 4B (Chido blood group), copy 2

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.

mRNA and Protein(s)

  1. NM_001242823.2 → NP_001229752.1  complement C4-B-like preproprotein

    See identical proteins and their annotated locations for NP_001229752.1

    Status: REVIEWED

    Source sequence(s)
    BX679671
    UniProtKB/TrEMBL
    A0A0G2JPR0
    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_2024_08

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

Reference GRCh38.p14 ALT_REF_LOCI_7

Genomic

  1. NT_167249.2 Reference GRCh38.p14 ALT_REF_LOCI_7

    Range
    3283246..3303870
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)
Nucleotide Protein
Heading Accession and Version

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