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C1QA complement C1q A chain [ Homo sapiens (human) ]

Gene ID: 712, updated on 5-Mar-2024

Summary

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Official Symbol
C1QAprovided by HGNC
Official Full Name
complement C1q A chainprovided by HGNC
Primary source
HGNC:HGNC:1241
See related
Ensembl:ENSG00000173372 MIM:120550; AllianceGenome:HGNC:1241
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
C1QD1
Summary
This gene encodes the A-chain polypeptide of serum complement subcomponent C1q, which associates with C1r and C1s to yield the first component of the serum complement system. C1q deficiency is associated with lupus erythematosus and glomerulonephritis. 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. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Nov 2016]
Expression
Broad expression in spleen (RPKM 445.5), lymph node (RPKM 179.4) and 16 other tissues See more
Orthologs
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Genomic context

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See C1QA in Genome Data Viewer
Location:
1p36.12
Exon count:
3
Annotation release Status Assembly Chr Location
RS_2023_10 current GRCh38.p14 (GCF_000001405.40) 1 NC_000001.11 (22636463..22639678)
RS_2023_10 current T2T-CHM13v2.0 (GCF_009914755.1) 1 NC_060925.1 (22461488..22464703)
105.20220307 previous assembly GRCh37.p13 (GCF_000001405.25) 1 NC_000001.10 (22962956..22966171)

Chromosome 1 - NC_000001.11Genomic Context describing neighboring genes Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:22890520-22891020 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr1:22898749-22899308 Neighboring gene EPH receptor A8 Neighboring gene Sharpr-MPRA regulatory region 15208 Neighboring gene microRNA 6127 Neighboring gene complement C1q C chain Neighboring gene complement C1q B chain

Genomic regions, transcripts, and products

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Go to nucleotide: Graphics FASTA GenBank

Expression

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  • 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

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Related articles in PubMed

  1. Complement protein C1q stimulates hyaluronic acid degradation via gC1qR/HABP1/p32 in malignant pleural mesothelioma. Balduit A, et al. Front Immunol, 2023. PMID 37334363, Free PMC Article
  2. Gene polymorphisms within regions of complement component C1q in HIV associated preeclampsia. Govender S, et al. Eur J Obstet Gynecol Reprod Biol, 2023 Mar. PMID 36716536
  3. Complement-Binding Donor-Specific Anti-HLA Antibodies: Biomarker for Immunologic Risk Stratification in Pediatric Kidney Transplantation Recipients. Sigurjonsdottir VK, et al. Transpl Int, 2022. PMID 35992747, Free PMC Article
  4. Serum complement C1q level is associated with left ventricular hypertrophy induced by coarctation of the aorta: A retrospective observational study. Chen L, et al. BMC Cardiovasc Disord, 2022 Aug 10. PMID 35948870, Free PMC Article
  5. SARS-CoV-2 Exacerbates COVID-19 Pathology Through Activation of the Complement and Kinin Systems. Savitt AG, et al. Front Immunol, 2021. PMID 34804054, Free PMC Article

See all (188) citations in PubMed

GeneRIFs: Gene References Into Functions

What's a GeneRIF?
  1. An integrative analysis of single-cell and bulk transcriptome and bidirectional mendelian randomization analysis identified C1Q as a novel stimulated risk gene for Atherosclerosis.
    Title: An integrative analysis of single-cell and bulk transcriptome and bidirectional mendelian randomization analysis identified C1Q as a novel stimulated risk gene for Atherosclerosis.
  2. Complement C1q and von Willebrand factor interaction in atherosclerosis of human carotid artery.
    Title: Complement C1q and von Willebrand factor interaction in atherosclerosis of human carotid artery.
  3. Association between serum complement 1q and the associated factors of acute ischemic stroke in patients with type 2 diabetes.
    Title: Association between serum complement 1q and the associated factors of acute ischemic stroke in patients with type 2 diabetes.
  4. Complement Activation-Independent Attenuation of SARS-CoV-2 Infection by C1q and C4b-Binding Protein.
    Title: Complement Activation-Independent Attenuation of SARS-CoV-2 Infection by C1q and C4b-Binding Protein.
  5. Complement protein C1q stimulates hyaluronic acid degradation via gC1qR/HABP1/p32 in malignant pleural mesothelioma.
    Title: Complement protein C1q stimulates hyaluronic acid degradation via gC1qR/HABP1/p32 in malignant pleural mesothelioma.
  6. Roles of mesangial C3 and C1q deposition in the clinical manifestations and prognosis of IgAN.
    Title: Roles of mesangial C3 and C1q deposition in the clinical manifestations and prognosis of IgAN.
  7. Gene polymorphisms within regions of complement component C1q in HIV associated preeclampsia.
    Title: Gene polymorphisms within regions of complement component C1q in HIV associated preeclampsia.
  8. Complement component C1q initiates extrinsic coagulation via the receptor for the globular head of C1q in adventitial fibroblasts and vascular smooth muscle cells.
    Title: Complement component C1q initiates extrinsic coagulation via the receptor for the globular head of C1q in adventitial fibroblasts and vascular smooth muscle cells.
  9. C1QA, C1QB, and GZMB are novel prognostic biomarkers of skin cutaneous melanoma relating tumor microenvironment.
    Title: C1QA, C1QB, and GZMB are novel prognostic biomarkers of skin cutaneous melanoma relating tumor microenvironment.
  10. Neuroinflammation and psychiatric disorders: Relevance of C1q, translocator protein (18 kDa) (TSPO), and neurosteroids.
    Title: Neuroinflammation and psychiatric disorders: Relevance of C1q, translocator protein (18 kDa) (TSPO), and neurosteroids.
Submit: New GeneRIF Correction See all GeneRIFs (109)

Phenotypes

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Find tests for this gene in the NIH Genetic Testing Registry (GTR)

Review eQTL and phenotype association data in this region using PheGenI

Associated conditions

Description Tests
C1Q deficiency 1
MedGen: CN376805 OMIM: 613652 GeneReviews: Not available
not available

Variation

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See variants in ClinVar

See studies and variants in dbVar

See Variation Viewer (GRCh37.p13)

See Variation Viewer (GRCh38)

Genotypes

HIV-1 interactions

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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

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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

Potential readthrough

Included gene: C1QC

Homology

Gene Ontology Provided by GOA

Function Evidence Code Pubs
enables amyloid-beta binding TAS
Traceable Author Statement
more info
 PubMed 
enables protein binding IPI
Inferred from Physical Interaction
more info
 PubMed 
Process Evidence Code Pubs
involved_in astrocyte activation ISS
Inferred from Sequence or Structural Similarity
more info
  
involved_in cell-cell signaling TAS
Traceable Author Statement
more info
 PubMed 
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 complement-mediated synapse pruning ISS
Inferred from Sequence or Structural Similarity
more info
  
involved_in innate immune response IEA
Inferred from Electronic Annotation
more info
  
involved_in microglial cell activation ISS
Inferred from Sequence or Structural Similarity
more info
  
involved_in neuron remodeling ISS
Inferred from Sequence or Structural Similarity
more info
  
involved_in synapse organization ISS
Inferred from Sequence or Structural Similarity
more info
  
involved_in synapse pruning ISS
Inferred from Sequence or Structural Similarity
more info
  
involved_in vertebrate eye-specific patterning ISS
Inferred from Sequence or Structural Similarity
more info
  
Component Evidence Code Pubs
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

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Preferred Names
complement C1q subcomponent subunit A
Names
complement C1q chain A
complement component 1, q subcomponent, A chain
complement component 1, q subcomponent, alpha polypeptide
complement component C1q, A chain

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_007282.1 RefSeqGene

    Range
    5001..8058
    Download
    GenBank, FASTA, Sequence Viewer (Graphics), LRG_22

mRNA and Protein(s)

  1. NM_001347465.2 → NP_001334394.1  complement C1q subcomponent subunit A precursor

    Status: REVIEWED

    Description
    Transcript Variant: This variant (2) represents the longest transcript. Variants 1-3 encode the same protein.
    Source sequence(s)
    BC030153, BC071986, BM920911, BX369252, DT215188
    Consensus CDS
    CCDS226.1
    UniProtKB/Swiss-Prot
    B2R4X2, P02745, Q5T963
    UniProtKB/TrEMBL
    A0A024RAG6, A0A3B0J657, X6RLJ0
    Related
    ENSP00000385564.1, ENST00000402322.2
    Conserved Domains (2) summary
    smart00110
    Location:108 → 244
    C1Q; Complement component C1q domain
    pfam01391
    Location:48 → 106
    Collagen; Collagen triple helix repeat (20 copies)

  2. NM_001347466.2 → NP_001334395.1  complement C1q subcomponent subunit A precursor

    Status: REVIEWED

    Description
    Transcript Variant: This variant (3) contains an alternate exon in the 5' UTR, compared to variant (2). Variants 1-3 encode the same protein.
    Source sequence(s)
    AL158086, BC071986, BI837739, BX369252
    Consensus CDS
    CCDS226.1
    UniProtKB/Swiss-Prot
    B2R4X2, P02745, Q5T963
    UniProtKB/TrEMBL
    A0A024RAG6, A0A3B0J657, X6RLJ0
    Related
    ENSP00000416841.2, ENST00000438241.2
    Conserved Domains (2) summary
    smart00110
    Location:108 → 244
    C1Q; Complement component C1q domain
    pfam01391
    Location:48 → 106
    Collagen; Collagen triple helix repeat (20 copies)

  3. NM_015991.4 → NP_057075.1  complement C1q subcomponent subunit A precursor

    See identical proteins and their annotated locations for NP_057075.1

    Status: REVIEWED

    Description
    Transcript Variant: This variant (1) uses an alternate splice site in the 5' UTR, compared to variant (2). Variants 1-3 encode the same protein.
    Source sequence(s)
    BC030153, BC071986, BG548439, BX369252
    Consensus CDS
    CCDS226.1
    UniProtKB/Swiss-Prot
    B2R4X2, P02745, Q5T963
    UniProtKB/TrEMBL
    A0A024RAG6, A0A3B0J657, X6RLJ0
    Related
    ENSP00000363773.3, ENST00000374642.8
    Conserved Domains (2) summary
    smart00110
    Location:108 → 244
    C1Q; Complement component C1q domain
    pfam01391
    Location:48 → 106
    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
    22636463..22639678
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

Alternate T2T-CHM13v2.0

Genomic

  1. NC_060925.1 Alternate T2T-CHM13v2.0

    Range
    22461488..22464703
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)
Nucleotide Protein
Heading Accession and Version
Protein Accession Links
GenPept Link UniProtKB Link
P02745.2 GenPept UniProtKB/Swiss-Prot:P02745

Gene LinkOut

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