Seroatlas · Human Serome Atlas

CTIF

CBP80/20-dependent translation initiation factor

Also known as: CTIF_HUMAN, KIAA0427

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

Protein identityUniProt · HPA

UniProt accession
O43310
Gene
CTIF
Ensembl
ENSG00000134030
Chromosome
18
Canonical length
598 aa
Protein class
Predicted intracellular proteins, Transporters
Subcellular location
Cytosol

OverviewNCBI Gene

CTIF is a component of the CBP80 (NCBP1; MIM 600469)/CBP20 (NCBP2; MIM 605133) translation initiation complex that binds cotranscriptionally to the cap end of nascent mRNA. The CBP80/CBP20 complex is involved in a simultaneous editing and translation step that recognizes premature termination codons (PTCs) in mRNAs and directs PTC-containing mRNAs toward nonsense-mediated decay (NMD). On mRNAs without PTCs, the CBP80/CBP20 complex is replaced with cytoplasmic mRNA cap-binding proteins, including EIF4G (MIM 600495), and steady-state translation of the mRNAs resumes in the cytoplasm (Kim et al., 2009 [PubMed 19648179]).[supplied by OMIM, Dec 2009]

Canonical amino-acid sequenceUniProt

598 residues, UniProt reviewed canonical sequence.

>O43310|CTIF
     1  MENSSAASAS SEAGSSRSQE IEELERFIDS YVLEYQVQGL LADKTEGDGE SERTQSHISQ
    61  WTADCSEPLD SSCSFSRGRA PPQQNGSKDN SLDMLGTDIW AANTFDSFSG ATWDLQPEKL
   121  DFTQFHRKVR HTPKQPLPHI DREGCGKGKL EDGDGINLND IEKVLPAWQG YHPMPHEVEI
   181  AHTKKLFRRR RNDRRRQQRP PGGNKPQQHG DHQPGSAKHN RDHQKSYQGG SAPHPSGRPT
   241  HHGYSQNRRW HHGNMKHPPG DKGEAGAHRN AKETMTIENP KLEDTAGDTG HSSLEAPRSP
   301  DTLAPVASER LPPQQSGGPE VETKRKDSIL PERIGERPKI TLLQSSKDRL RRRLKEKDEV
   361  AVETTTPQQN KMDKLIEILN SMRNNSSDVD TKLTTFMEEA QNSTNSEEML GEIVRTIYQK
   421  AVSDRSFAFT AAKLCDKMAL FMVEGTKFRS LLLNMLQKDF TVREELQQQD VERWLGFITF
   481  LCEVFGTMRS STGEPFRVLV CPIYTCLREL LQSQDVKEDA VLCCSMELQS TGRLLEEQLP
   541  EMMTELLASA RDKMLCPSES MLTRSLLLEV IELHANSWNP LTPPITQYYN RTIQKLTA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CTIF 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)
0.48
Highest tissue expression
43 nTPM

Expression across tissuesHPA

Tissue

  • cerebral cortex: 43 nTPM
  • cerebellum: 37 nTPM
  • blood vessel: 36 nTPM
  • hypothalamus: 35 nTPM
  • adipose tissue: 33 nTPM
  • basal ganglia: 33 nTPM

Single-cell type

  • other brain neurons: 168 nCPM
  • astrocytes: 165 nCPM
  • bergmann glia: 150 nCPM
  • oligodendrocyte progenitor cells: 125 nCPM
  • brain inhibitory neurons: 125 nCPM
  • brain excitatory neurons: 121 nCPM

Immune cell

  • basophil: 0.1 nTPM
  • eosinophil: 0.1 nTPM
  • gdT-cell: 0.1 nTPM
  • myeloid DC: 0.1 nTPM
  • classical monocyte: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • pons: 72 nTPM
  • cerebral cortex: 69 nTPM
  • medulla oblongata: 61 nTPM
  • thalamus: 61 nTPM
  • midbrain: 60 nTPM
  • white matter: 55 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)
0.11
gnomAD pLI
1
gnomAD missense Z
1.49
DepMap mean gene effect
0.16
DepMap dependency class
none

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

Antibody and autoantibody relevanceSeroatlas analysis

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

CTIF 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 CTIF as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CTIF. 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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