Seroatlas · Human Serome Atlas

EIF2S1

Eukaryotic translation initiation factor 2 subunit 1

Also known as: EIF-2alpha, EIF2, EIF2A, IF2A_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P05198
Gene
EIF2S1
Ensembl
ENSG00000134001
Chromosome
14
Canonical length
315 aa
Protein class
Plasma proteins, Predicted intracellular proteins
Subcellular location
Cytosol

OverviewNCBI Gene

The translation initiation factor EIF2 catalyzes the first regulated step of protein synthesis initiation, promoting the binding of the initiator tRNA to 40S ribosomal subunits. Binding occurs as a ternary complex of methionyl-tRNA, EIF2, and GTP. EIF2 is composed of 3 nonidentical subunits, the 36-kD EIF2-alpha subunit (EIF2S1), the 38-kD EIF2-beta subunit (EIF2S2; MIM 603908), and the 52-kD EIF2-gamma subunit (EIF2S3; MIM 300161). The rate of formation of the ternary complex is modulated by the phosphorylation state of EIF2-alpha (Ernst et al., 1987 [PubMed 2948954]).[supplied by OMIM, Feb 2010]

Canonical amino-acid sequenceUniProt

315 residues, UniProt reviewed canonical sequence.

>P05198|EIF2S1
     1  MPGLSCRFYQ HKFPEVEDVV MVNVRSIAEM GAYVSLLEYN NIEGMILLSE LSRRRIRSIN
    61  KLIRIGRNEC VVVIRVDKEK GYIDLSKRRV SPEEAIKCED KFTKSKTVYS ILRHVAEVLE
   121  YTKDEQLESL FQRTAWVFDD KYKRPGYGAY DAFKHAVSDP SILDSLDLNE DEREVLINNI
   181  NRRLTPQAVK IRADIEVACY GYEGIDAVKE ALRAGLNCST ENMPIKINLI APPRYVMTTT
   241  TLERTEGLSV LSQAMAVIKE KIEEKRGVFN VQMEPKVVTD TDETELARQM ERLERENAEV
   301  DGDDDAEEME AKAED

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against EIF2S1 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)
0.34
Highest tissue expression
48 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 48 nTPM
  • tongue: 38 nTPM
  • esophagus: 37 nTPM
  • urinary bladder: 36 nTPM
  • liver: 33 nTPM
  • tonsil: 31 nTPM

Single-cell type

  • early primary spermatocytes: 211 nCPM
  • oocytes: 166 nCPM
  • suprabasal keratinocytes: 159 nCPM
  • late primary spermatocytes: 156 nCPM
  • esophageal suprabasal cells: 155 nCPM
  • basal keratinocytes: 152 nCPM

Immune cell

  • intermediate monocyte: 71 nTPM
  • total PBMC: 71 nTPM
  • myeloid DC: 70 nTPM
  • T-reg: 65 nTPM
  • non-classical monocyte: 63 nTPM
  • NK-cell: 59 nTPM

Brain region

  • white matter: 32 nTPM
  • cerebral cortex: 30 nTPM
  • cerebellum: 29 nTPM
  • hypothalamus: 27 nTPM
  • medulla oblongata: 27 nTPM
  • basal ganglia: 27 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)
0.31
gnomAD pLI
0.97
gnomAD missense Z
2.86
DepMap mean gene effect
-1.81
DepMap dependency class
pan

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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

  • S1 domain
  • Nucleic acid-binding, OB-fold
  • S1 RNA binding domain
  • Translation initiation factor 2, alpha subunit
  • Translation initiation factor 2, alpha subunit, middle domain superfamily
  • Translation initiation factor 2, alpha subunit, C-terminal
  • IF2a, S1-like domain
  • Eukaryotic translation initiation factor 2 alpha subunit

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of EIF2S1 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 EIF2S1 as an antibody target. Whether an autoantibody or antibody against EIF2S1 could matter depends on whether native EIF2S1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

EIF2S1 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 EIF2S1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/EIF2S1. 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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