Seroatlas · Human Serome Atlas

CCNT1

Cyclin-T1

Also known as: CCNT, CCNT1_HUMAN, CYCT1, HIVE1

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
O60563
Gene
CCNT1
Ensembl
ENSG00000129315
Chromosome
12
Canonical length
726 aa
Protein class
Plasma proteins, Predicted intracellular proteins
Subcellular location
Nucleoplasm

OverviewNCBI Gene

This gene encodes a member of the highly conserved cyclin C subfamily. The encoded protein tightly associates with cyclin-dependent kinase 9, and is a major subunit of positive transcription elongation factor b (p-TEFb). In humans, there are multiple forms of positive transcription elongation factor b, which may include one of several different cyclins along with cyclin-dependent kinase 9. The complex containing the encoded cyclin and cyclin-dependent kinase 9 acts as a cofactor of human immunodeficiency virus type 1 (HIV-1) Tat protein, and is both necessary and sufficient for full activation of viral transcription. This cyclin and its kinase partner are also involved in triggering transcript elongation through phosphorylation of the carboxy-terminal domain of the largest RNA polymerase II subunit. Overexpression of this gene is implicated in tumor growth. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Apr 2013]

Canonical amino-acid sequenceUniProt

726 residues, UniProt reviewed canonical sequence.

>O60563|CCNT1
     1  MEGERKNNNK RWYFTREQLE NSPSRRFGVD PDKELSYRQQ AANLLQDMGQ RLNVSQLTIN
    61  TAIVYMHRFY MIQSFTQFPG NSVAPAALFL AAKVEEQPKK LEHVIKVAHT CLHPQESLPD
   121  TRSEAYLQQV QDLVILESII LQTLGFELTI DHPHTHVVKC TQLVRASKDL AQTSYFMATN
   181  SLHLTTFSLQ YTPPVVACVC IHLACKWSNW EIPVSTDGKH WWEYVDATVT LELLDELTHE
   241  FLQILEKTPN RLKRIWNWRA CEAAKKTKAD DRGTDEKTSE QTILNMISQS SSDTTIAGLM
   301  SMSTSTTSAV PSLPVSEESS SNLTSVEMLP GKRWLSSQPS FKLEPTQGHR TSENLALTGV
   361  DHSLPQDGSN AFISQKQNSK SVPSAKVSLK EYRAKHAEEL AAQKRQLENM EANVKSQYAY
   421  AAQNLLSHHD SHSSVILKMP IEGSENPERP FLEKADKTAL KMRIPVAGGD KAASSKPEEI
   481  KMRIKVHAAA DKHNSVEDSV TKSREHKEKH KTHPSNHHHH HNHHSHKHSH SQLPVGTGNK
   541  RPGDPKHSSQ TSNLAHKTYS LSSSFSSSSS TRKRGPSEET GGAVFDHPAK IAKSTKSSSL
   601  NFSFPSLPTM GQMPGHSSDT SGLSFSQPSC KTRVPHSKLD KGPTGANGHN TTQTIDYQDT
   661  VNMLHSLLSA QGVQPTQPTA FEFVRPYSDY LNPRSGGISS RSGNTDKPRP PPLPSEPPPP
   721  LPPLPK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CCNT1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.53
Highest tissue expression
28 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 28 nTPM
  • thymus: 12 nTPM
  • retina: 11 nTPM
  • thyroid gland: 11 nTPM
  • lymph node: 11 nTPM
  • parathyroid gland: 11 nTPM

Single-cell type

  • early spermatids: 172 nCPM
  • neutrophils: 135 nCPM
  • nk-cells: 112 nCPM
  • t-cells: 96 nCPM
  • hematopoietic stem cells: 88 nCPM
  • innate lymphoid cells: 87 nCPM

Immune cell

  • neutrophil: 14 nTPM
  • basophil: 9 nTPM
  • eosinophil: 7.8 nTPM
  • naive B-cell: 5.4 nTPM
  • MAIT T-cell: 4.5 nTPM
  • plasmacytoid DC: 4.4 nTPM

Brain region

  • hypothalamus: 24 nTPM
  • choroid plexus: 22 nTPM
  • white matter: 20 nTPM
  • cerebellum: 20 nTPM
  • thalamus: 19 nTPM
  • cerebral cortex: 19 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
0.5
gnomAD pLI
0.05
gnomAD missense Z
1.08
DepMap mean gene effect
-0.27
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of CCNT1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CCNT1 as an antibody target. Whether an autoantibody or antibody against CCNT1 could matter depends on whether native CCNT1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CCNT1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label CCNT1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CCNT1. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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