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C1QB complement C1q B chain [ Homo sapiens (human) ]

Gene ID: 713, updated on 5-Mar-2024

Summary

Official Symbol
C1QBprovided by HGNC
Official Full Name
complement C1q B chainprovided by HGNC
Primary source
HGNC:HGNC:1242
See related
Ensembl:ENSG00000173369 MIM:120570; AllianceGenome:HGNC:1242
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
C1QD2
Summary
This gene encodes the B-chain polypeptide of serum complement subcomponent C1q, which associates with C1r and C1s to yield the first component of the serum complement system. C1q is composed of 18 polypeptide chains which include 6 A-chains, 6 B-chains, and 6 C-chains. Each chain contains an N-terminal collagen-like region and a C-terminal C1q globular domain. C1q deficiency is associated with lupus erythematosus and glomerulonephritis. [provided by RefSeq, Dec 2016]
Expression
Broad expression in spleen (RPKM 482.2), lymph node (RPKM 181.6) and 15 other tissues See more
Orthologs
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Genomic context

Location:
1p36.12
Exon count:
4
Annotation release Status Assembly Chr Location
RS_2023_10 current GRCh38.p14 (GCF_000001405.40) 1 NC_000001.11 (22653236..22661637)
RS_2023_10 current T2T-CHM13v2.0 (GCF_009914755.1) 1 NC_060925.1 (22478246..22486577)
105.20220307 previous assembly GRCh37.p13 (GCF_000001405.25) 1 NC_000001.10 (22979729..22988130)

Chromosome 1 - NC_000001.11Genomic Context describing neighboring genes Neighboring gene complement C1q A chain Neighboring gene complement C1q C chain Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr1:23003627-23004149 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23004182-23004720 Neighboring gene H3K27ac hESC enhancer GRCh37_chr1:23021074-23021574 Neighboring gene H3K27ac hESC enhancer GRCh37_chr1:23021575-23022075 Neighboring gene ReSE screen-validated silencer GRCh37_chr1:23036019-23036304 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 353 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23043657-23044346 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23049783-23050297 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23063222-23063783 Neighboring gene EPH receptor B2 Neighboring gene microRNA 4684 Neighboring gene ReSE screen-validated silencer GRCh37_chr1:23066264-23066434 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 354 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 355 Neighboring gene ReSE screen-validated silencer GRCh37_chr1:23082861-23083022 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23117273-23117773 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23118959-23119488 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23136274-23136774 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23136775-23137275 Neighboring gene Sharpr-MPRA regulatory region 697 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23154258-23154779 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr1:23163087-23164034 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23176387-23176888 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23176889-23177388 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23179771-23180334 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:23180335-23180896 Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 403 Neighboring gene microRNA 4253

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?

HIV-1 interactions

Protein interactions

Protein Gene Interaction Pubs
Envelope surface glycoprotein gp120 env Fibronectin, which is present in submandibular saliva, binds to HIV-1 gp120/160 and enhances the interaction of C1q with gp120/160 PubMed
env Free C1q binds to HIV-1 gp120; digestion of the C1q stem portion with collagenase completely eliminates its binding to recombinant gp120, suggesting that the collagen-like stem region of C1q participates in the binding to gp120 PubMed
Envelope transmembrane glycoprotein gp41 env The interaction between C1q and HIV-gp41 is dependent upon the presence of calcium; calcium can not be replaced by larger cations such as strontium, barium, lead or smaller ions such as magnesium and manganese PubMed
env HIV-1 gp41 (amino acid residues 561-575, 591-605 and 601-620) binds to complement C1q and activates the C1 complex in a dose- and time-dependent manner PubMed
env Three sites (amino acids 526-538, 590-613 and 625-655) of the cell-external part of HIV-1 gp41 bind both HIV-1 gp120 and C1q 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

Gene Ontology Provided by GOA

Function Evidence Code Pubs
enables protein binding IPI
Inferred from Physical Interaction
more info
PubMed 
Process Evidence Code Pubs
involved_in complement activation TAS
Traceable Author Statement
more info
PubMed 
involved_in complement activation, classical pathway IDA
Inferred from Direct Assay
more info
PubMed 
involved_in complement activation, classical pathway NAS
Non-traceable Author Statement
more info
PubMed 
involved_in innate immune response IEA
Inferred from Electronic Annotation
more info
 
involved_in synapse pruning ISS
Inferred from Sequence or Structural Similarity
more info
 
Component Evidence Code Pubs
located_in blood microparticle HDA PubMed 
part_of collagen trimer IEA
Inferred from Electronic Annotation
more info
 
located_in collagen-containing extracellular matrix HDA PubMed 
part_of complement component C1 complex NAS
Non-traceable Author Statement
more info
PubMed 
part_of complement component C1q complex IPI
Inferred from Physical Interaction
more info
PubMed 
located_in extracellular region IDA
Inferred from Direct Assay
more info
PubMed 
located_in extracellular region NAS
Non-traceable Author Statement
more info
PubMed 
located_in extracellular region TAS
Traceable Author Statement
more info
 
located_in postsynapse ISS
Inferred from Sequence or Structural Similarity
more info
 
located_in synapse ISS
Inferred from Sequence or Structural Similarity
more info
 

General protein information

Preferred Names
complement C1q subcomponent subunit B
Names
complement C1q chain B
complement component 1, q subcomponent, B chain
complement component 1, q subcomponent, beta polypeptide
complement component C1q, B chain
complement subcomponent C1q chain B

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_007283.1 RefSeqGene

    Range
    5001..13348
    Download
    GenBank, FASTA, Sequence Viewer (Graphics), LRG_23

mRNA and Protein(s)

  1. NM_000491.5NP_000482.3  complement C1q subcomponent subunit B isoform 1 precursor

    See identical proteins and their annotated locations for NP_000482.3

    Status: REVIEWED

    Description
    Transcript Variant: This variant (2) differs in the 5' UTR, compared to variant 1. Variants 1 and 2 encode the same protein.
    Source sequence(s)
    AL158086
    UniProtKB/Swiss-Prot
    P02746, Q5T959, Q96H17
    UniProtKB/TrEMBL
    A0A024RAB9, A0A3B0J0A0, A0A8Q3SI33
    Conserved Domains (2) summary
    smart00110
    Location:115250
    C1Q; Complement component C1q domain
    pfam01391
    Location:3386
    Collagen; Collagen triple helix repeat (20 copies)
  2. NM_001371184.3NP_001358113.2  complement C1q subcomponent subunit B isoform 2 precursor

    Status: REVIEWED

    Description
    Transcript Variant: This variant (1) represents the longer transcript and encodes isoform 2
    Source sequence(s)
    AA838059, AI125081, BI489644, BQ711602, X03084
    Consensus CDS
    CCDS90878.1
    UniProtKB/TrEMBL
    A0A8Q3SI33, D6R934
    Related
    ENSP00000404606.2, ENST00000432749.6
    Conserved Domains (2) summary
    smart00110
    Location:113248
    C1Q; Complement component C1q domain
    pfam01391
    Location:3786
    Collagen; Collagen triple helix repeat (20 copies)
  3. NM_001378156.1NP_001365085.1  complement C1q subcomponent subunit B isoform 2 precursor

    Status: REVIEWED

    Source sequence(s)
    AL158086
    Consensus CDS
    CCDS90878.1
    UniProtKB/TrEMBL
    A0A8Q3SI33, D6R934
    Related
    ENSP00000423689.1, ENST00000509305.6
    Conserved Domains (2) summary
    smart00110
    Location:113248
    C1Q; Complement component C1q domain
    pfam01391
    Location:3786
    Collagen; Collagen triple helix repeat (20 copies)

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_000001.11 Reference GRCh38.p14 Primary Assembly

    Range
    22653236..22661637
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

Alternate T2T-CHM13v2.0

Genomic

  1. NC_060925.1 Alternate T2T-CHM13v2.0

    Range
    22478246..22486577
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)