Detailed entry information

Protein Information (annotations from UniProt)

Database IDHIV0000360
UniProt IDQ07021
Primary gene name(s)C1QBP
Synonym gene name(s)GC1QBP, HABP1, SF2P32
Protein nameComplement component 1 Q subcomponent-binding protein, mitochondrial
Protein functionIs believed to be a multifunctional and multicompartmental protein involved in inflammation and infection processes, ribosome biogenesis, regulation of apoptosis, transcriptional regulation and pre-mRNA splicing. At the cell surface is thought to act as an endothelial receptor for plasma proteins of the complement and kallikrein-kinin cascades. Putative receptor for C1q; specifically binds to the globular ""heads"" of C1q thus inhibiting C1; may perform the receptor function through a complex with C1qR/CD93. In complex with cytokeratin-1/KRT1 is a high affinity receptor for kininogen-1/HMWK. Can also bind other plasma proteins, such as coagulation factor XII leading to its autoactivation. May function to bind initially fluid kininogen-1 to the cell membrane. The secreted form may enhance both extrinsic and intrinsic coagulation pathways. It is postulated that the cell surface form requires docking with transmembrane proteins for downstream signaling which might be specific for a cell-type or response. By acting as C1q receptor is involved in chemotaxis of immature dendritic cells and neutrophils and is proposed to signal through CD209/DC-SIGN on immature dendritic cells, through integrin alpha-4/beta-1 during trophoblast invasion of the decidua, and through integrin beta-1 during endothelial cell adhesion and spreading. Signaling involved in inhibition of innate immune response is implicating the PI3K-AKT/PKB pathway. In mitochondrial translation may be involved in formation of functional 55S mitoribosomes; the function seems to involve its RNA-binding activity. May be involved in the nucleolar ribosome maturation process; the function may involve the exchange of FBL for RRP1 in the association with pre-ribosome particles. Involved in regulation of RNA splicing by inhibiting the RNA-binding capacity of SRSF1 and its phosphorylation. Is required for the nuclear translocation of splicing factor U2AF1L4. Involved in regulation of CDKN2A- and HRK-mediated apoptosis. Stabilizes mitochondrial CDKN2A isoform smARF. May be involved in regulation of FOXC1 transcriptional activity and NFY/CCAAT-binding factor complex-mediated transcription. In infection processes acts as an attachment site for microbial proteins, including Listeria monocytogenes internalin B and Staphylococcus aureus protein A. May play a role in antibacterial defense as it can bind to cell surface hyaluronan and inhibit Streptococcus pneumoniae hyaluronate lyase. Involved in replication of Rubella virus. May be involved in modulation of the immune response; ligation by HCV core protein is resulting in suppresion of interleukin-12 production in monocyte-derived dendritic cells. Involved in regulation of antiviral response by inhibiting DDX58- and IFIH1-mediated signaling pathways probably involving its association with MAVS after viral infection. Involved in HIV-1 replication, presumably by contributing to splicing of viral RNA. {ECO:0000269|PubMed:10022843, ECO:0000269|PubMed:10479529, ECO:0000269|PubMed:10722602, ECO:0000269|PubMed:10747014, ECO:0000269|PubMed:11086025, ECO:0000269|PubMed:11859136, ECO:0000269|PubMed:12833064, ECO:0000269|PubMed:15243141, ECO:0000269|PubMed:16140380, ECO:0000269|PubMed:16177118, ECO:0000269|PubMed:17881511, ECO:0000269|PubMed:18676636, ECO:0000269|PubMed:19004836, ECO:0000269|PubMed:19164550, ECO:0000269|PubMed:20810993, ECO:0000269|PubMed:21536856, ECO:0000269|PubMed:21544310, ECO:0000269|PubMed:22700724, ECO:0000269|PubMed:8662673, ECO:0000269|PubMed:8710908, ECO:0000269|PubMed:9461517}."
Subcellular locationMitochondrion matrix. Nucleus. Cell membrane;
Peripheral membrane protein;
Extracellular side. Secreted. Cytoplasm. Nucleus, nucleolus. Note=Seems to be predominantly localized to mitochondria. Secreted by activated lymphocytes.
ECO codeClick here for more information.
Amino acid sequence
FASTA format: Q07021
Gene Ontology
(Biological Process)
Complete annatation
apoptotic process [GO:0006915];
blood coagulation, intrinsic pathway [GO:0007597];
complement activation, classical pathway [GO:0006958];
immune response [GO:0006955];
innate immune response [GO:0045087];
mature ribosome assembly [GO:0042256];
mRNA processing [GO:0006397];
negative regulation of defense response to virus [GO:0050687];
negative regulation of interferon-gamma production [GO:0032689];
negative regulation of interleukin-12 production [GO:0032695];
negative regulation of MDA-5 signaling pathway [GO:0039534];
negative regulation of mRNA splicing, via spliceosome [GO:0048025];
negative regulation of RIG-I signaling pathway [GO:0039536];
negative regulation of transcription from RNA polymerase II promoter [GO:0000122];
phosphatidylinositol 3-kinase signaling [GO:0014065];
positive regulation of apoptotic process [GO:0043065];
positive regulation of cell adhesion [GO:0045785];
positive regulation of dendritic cell chemotaxis [GO:2000510];
positive regulation of mitochondrial translation [GO:0070131];
positive regulation of neutrophil chemotaxis [GO:0090023];
positive regulation of protein kinase B signaling [GO:0051897];
positive regulation of substrate adhesion-dependent cell spreading [GO:1900026];
positive regulation of trophoblast cell migration [GO:1901165];
regulation of complement activation [GO:0030449];
RNA splicing [GO:0008380];
transcription, DNA-templated [GO:0006351];
viral process [GO:0016032]
Gene Ontology
(Molecular Function)
Complete annatation
adrenergic receptor binding [GO:0031690];
complement component C1q binding [GO:0001849];
hyaluronic acid binding [GO:0005540];
kininogen binding [GO:0030984];
mitochondrial ribosome binding [GO:0097177];
mRNA binding [GO:0003729];
transcription corepressor activity [GO:0003714];
transcription factor binding [GO:0008134]
Gene Ontology
(Cellular Component)
Complete annatation
cell surface [GO:0009986];
cytoplasm [GO:0005737];
cytosol [GO:0005829];
extracellular space [GO:0005615];
membrane [GO:0016020];
mitochondrial matrix [GO:0005759];
mitochondrion [GO:0005739];
nucleolus [GO:0005730];
nucleus [GO:0005634];
plasma membrane [GO:0005886]
Protein-protein interaction107169
Phylogenetic treeQ07021
HIV replication factor status Zhou et al., Cell. Host. Microbe., 2008
      unknown
Brass et al., Science, 2008
      unknown
Smith et al., J. Immunol, 2010
      unknown
Interferon-stimulated
gene status
Lu et al., J. Virol., 2011
      Folds changes 8h: unknown; Folds changes 16h: unknown; Tested: unknown;
Schoggins JW and Rice CM, Curr. Opin. Virol., 2011
      Targeted viruses: unknown
      Viral life cycle: unknown
      Mechanism related to antiviral activity: unknown
Anti-viral restriction factor Liu et al., Retrovirology, 2011
      unknown (Triplicates)

Gene Expression Profile       top

            Up-regulated;            Down-regulated

For brief introduction to each study, please go to the help page.

Gene expression during HIV latency

(1). Mohammadi et al., PLoS Pathog., 2014

Differentially expressed transcripts (Pairwise) during latency and subsequent viral reactivation using several agents - Primary CD4+ T-cell based model


DMSO: Dimethyl suloxyde (negative control) - 0.0033% final
SAHA: Vorinostat (Histone deacetylase inhibitor) - 0.5 μM
CD3: TCR Stimulation by IL-2+ antiCD3/anti-CD28 antibodies
IL7: Interleukin-7 based stimulation
DISU: Disulfiram (alcohol dehydrogenase inhibitor) - 0.5 μM
AZA: 5-azacytidine (AZA; DNA methylation inhibitor) - 1 μM
Experimental Condition Log2 Fold Change P value Adjusted P value
AZA vs. CD31.807485943314168.45261455273416e-088.28334242775093e-07
AZA vs. DISU-0.354687148176240.1619391297119660.745592682125283
AZA vs. IL70.4506142672902140.01932485804225930.448120182249839
AZA vs. SAHA-0.4847565548406560.04766897768969890.262728398425785
DISU vs. CD3-2.174371572541689.77673964008829e-091.50998538252757e-07
DISU vs. IL70.796464307960350.001698427440375850.0381361509195381
DISU vs. SAHA-0.1291211998975350.6588537958084290.895348200761579
DMSO vs. AZA-0.1148151418008340.4939107195842291
DMSO vs. CD3-1.93434081326535.01733599111986e-095.69601859127511e-08
DMSO vs. DISU0.2377876242830150.3306841822613030.831763865574459
DMSO vs. IL70.5728402446808420.001498078720881370.0733269044585101
DMSO vs. SAHA-0.3767360278665870.1109762658620460.395431461167372
HIV vs. Mock in Activation-0.164654022567220.791257906487290.999983755607037
HIV vs. Mock in Latency-0.2420466449852640.144422604043540.999834320637052
IL7 vs. CD3-1.348284952693983.63836782095728e-050.00024042577012402
SAHA vs. CD3-2.317307092752883.85158460680657e-107.09576772916565e-09
SAHA vs. IL7-0.9387972819214060.000132350094771860.00244490849092037
(2). Iglesias-Ussel et al., J. Virol., 2013

Up and Downregulated transcripts during Latency (Latently infected CD4+ T cells vs Uninfected)- Primary CD4+Tcell based model
Log2 Fold Change P Value
-0.4491 0.03943

Gene expression during HIV infection and replication

(1). Imbeault et al., PloS Pathog., 2012

Transcriptomic profiling of HIV-1 infected CD4+ T cells - Primary CD4+ T cells
Experiment type Log2 Fold Change P Value Adjusted P Value
Infected vs. Mock unknown unknown unknown
Infected vs. Bystander unknown unknown unknown
(2). Lefebvre et al., J. Virol., 2011

Transcriptome analysis of T-cell line (Sup T1)
Log2 Fold Change unknown
(3). Li et al., J. Immunol., 2013

Lymphatic tissue
Acute Fold Change Acute P Value Asymt Fold Change Asypt P Value AIDS Fold Change AIDS P Value
1.7 0.00182001 1.1 0.212570415 1.2 0.402016355
(4). Chang et al., MBio., 2011

Transcriptome analysis of T-cell line (Sup T1)

Derived from Sherrill-Mix et al., BMC Retrovirol., 2015 cross validation
Up-regulated (True) FALSE
(5). Sherrill-Mix et al., BMC Retrovirol., 2015

Deep RNA-seq analysis of primary human T cell infected with low passage HIV isolate HIV89.6 - Primary CD4+ T cell based
Test Status Log2 Fold Change P Value
OK 0.10072 0.712989
(6). Rotger et al., PLoS Pathog., 2010

Genome-wide mRNA expression of CD4+ T cells from HIV-infected patient
(Genes differentially expressed (at adjusted p<0.01) according to the empirical Bayes approach)
Log2 Fold Change P Value
unknown unknown

Proteomic/Transcriptomics studies indicating differentially expressed genes mediated by HIV

(1). Greenwood et al., Elife, 2016

Activated (CD3/CD28) Primary human CD4+ T cells infected with pNL4-3-dE-EGFP. The table shows the complete (unfiltered) TMT (tandem mass tag)-based proteomic time course dataset
6 h 24 h 48 h 72 h RTi
0.996 0.991 0.978 0.887 0.794
(2). Navare et al., Virology, 2012

SUP-T1 cell line
FC-4hpi P-value FC-8hpi P-value FC-20hpi P-value Category
0.66 0.0007 -0.5 0.0165 -0.17 0.1023 Cell growth and proliferation at 4 hpi
(3). Hyrcza et al., J. Virolo., 2007

Primary human CD4+ and CD8+ T Cells
Affymetrix Prob ID Fold Change In CD8? Category
unknown unknown unknown unknown

Protein Overview       top

Drug-protein Interaction       (annotations from DrugBank)      top

Drugbank ID Drug Name Drug Status Pharmacological Action Drug Action
DB08818 Hyaluronic acid approved, vet_approved unknown binder

Protein Secondary Structure       (annotations from PDB)      top

PDB Accession Method Resolution Chain Structure Preview
1P32 X-ray 2.2Å A/B/C=74-282.
3RPX X-ray 2.6Å A/B/C=96-282.

HIV-1 Interaction       (annotations from NCBI HIV-1 Interaction Database)      top

HIV Partner Interaction Type PubMed
Rev binds 12833064
8189522
86265638626563
19149558
Vpr downregulates 23874603
Rev inhibits 8626563
12833064
19149558
Tat binds 16537587
194540107778269
Envelope surface glycoprotein gp120 upregulates 17676665
Envelope transmembrane glycoprotein gp41 activates 20617170

Metabolic/Signalling Pathway       (annotations from KEGG database)      top

Pathway Accession Number Description
hsa05168 Herpes simplex infection - Homo sapiens (human)
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