Detailed entry information

Protein Information (annotations from UniProt)

Database IDHIV0000332
UniProt IDQ2NKJ3
Primary gene name(s)CTC1
Synonym gene name(s)C17orf68
Protein nameCST complex subunit CTC1
Protein functionComponent of the CST complex proposed to act as a specialized replication factor promoting DNA replication under conditions of replication stress or natural replication barriers such as the telomere duplex. The CST complex binds single-stranded DNA with high affinity in a sequence-independent manner, while isolated subunits bind DNA with low affinity by themselves. Initially the CST complex has been proposed to protect telomeres from DNA degradation, PubMed:19854130. However, the CST complex has been shown to be involved in several aspects of telomere replication. The CST complex inhibits telomerase and is involved in telomere length homeostasis; it is proposed to bind to newly telomerase-synthesized 3' overhangs and to terminate telomerase action implicating the association with the ACD:POT1 complex thus interfering with its telomerase stimulation activity. The CST complex is also proposed to be involved in fill-in synthesis of the telomeric C-strand probably implicating recruitment and activation of DNA polymerase alpha, PubMed:22763445. The CST complex facilitates recovery from many forms of exogenous DNA damage; seems to be involved in the re-initiation of DNA replication at repaired forks and/or dormant origins, PubMed:25483097. Involved in telomere maintenance, PubMed:19854131, PubMed:22863775. Involved in genome stability, PubMed:22863775. May be in involved in telomeric C-strand fill-in during late S/G2 phase, By similarity. {ECO:0000250|UniProtKB:Q5SUQ9, ECO:0000269|PubMed:19854130, ECO:0000269|PubMed:19854131, ECO:0000269|PubMed:22763445, ECO:0000269|PubMed:22863775, ECO:0000269|PubMed:25483097}.
Subcellular locationNucleus {ECO:0000269|PubMed:19854130}. Chromosome, telomere {ECO:0000269|PubMed:19854130}. Note=A transmembrane region is predicted by sequence analysis tools, ESKW, MEMSAT and Phobius;
however, given the telomeric localization of the protein, the relevance of the transmembrane region is unsure in vivo. {ECO:0000305}.
ECO codeClick here for more information.
Amino acid sequence
FASTA format: Q2NKJ3
Gene Ontology
(Biological Process)
Complete annatation
bone marrow development [GO:0048539];
cellular response to DNA damage stimulus [GO:0006974];
hematopoietic stem cell proliferation [GO:0071425];
multicellular organism growth [GO:0035264];
negative regulation of telomerase activity [GO:0051974];
positive regulation of DNA replication [GO:0045740];
positive regulation of fibroblast proliferation [GO:0048146];
regulation of G2/M transition of mitotic cell cycle [GO:0010389];
regulation of telomere maintenance via telomere lengthening [GO:1904356];
replicative senescence [GO:0090399];
spleen development [GO:0048536];
telomere maintenance [GO:0000723];
telomere maintenance via telomere lengthening [GO:0010833];
thymus development [GO:0048538]
Gene Ontology
(Molecular Function)
Complete annatation
G-rich strand telomeric DNA binding [GO:0098505];
single-stranded DNA binding [GO:0003697];
telomeric DNA binding [GO:0042162]
Gene Ontology
(Cellular Component)
Complete annatation
CST complex [GO:1990879];
nuclear chromosome, telomeric region [GO:0000784];
nucleus [GO:0005634]
Protein-protein interaction123155
Phylogenetic treeQ2NKJ3
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. CD3-1.503712925318957.20461509229331e-064.59923586069652e-05
AZA vs. DISU0.1318985308030080.601569261123670.955158276076142
AZA vs. IL7-0.2261350759671930.2391583319658970.991155770613681
AZA vs. SAHA0.130507004166580.592503943277840.865914152139144
DISU vs. CD31.621685740018461.28940963691759e-059.33104218285924e-05
DISU vs. IL7-0.3671244191094470.1449535495020650.495999426255391
DISU vs. SAHA0.001124358468918420.9969176598268020.999572425883731
DMSO vs. AZA0.1586854915886530.3426779787812151
DMSO vs. CD31.648361465384915.26740038697682e-073.97761337492761e-06
DMSO vs. DISU0.02445685513173130.9200277177423340.988899823982894
DMSO vs. IL7-0.3772114213162510.03591005810736580.388060305353792
DMSO vs. SAHA-0.0332917321151260.887634440542690.972686978140092
HIV vs. Mock in Activation0.3985095148994810.5226722091569360.999983755607037
HIV vs. Mock in Latency0.05828215159524840.7234191133445010.999834320637052
IL7 vs. CD31.283578611789038.56932243344932e-050.000508325057219133
SAHA vs. CD31.610639202878478.51161632475783e-065.44439974592956e-05
SAHA vs. IL70.3533343998116340.1469524086175260.361895214425844
(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
unknown unknown

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
unknown unknown unknown unknown unknown unknown
(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) TRUE
(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 -0.109986 0.493856
(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
1.157 1.898 2.032 1.868 2.28
(2). Navare et al., Virology, 2012

SUP-T1 cell line
FC-4hpi P-value FC-8hpi P-value FC-20hpi P-value Category
unknown unknown unknown unknown unknown unknown unknown
(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

not found

Protein Secondary Structure       (annotations from PDB)      top

not found

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

not found

Metabolic/Signalling Pathway       (annotations from KEGG database)      top

Pathway Accession Number Description
not found
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