Seroatlas · Human Serome Atlas

IARS1

Isoleucine--tRNA ligase, cytoplasmic

Also known as: IARS, ILRS, SYIC_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P41252
Gene
IARS1
Ensembl
ENSG00000196305
Chromosome
9
Canonical length
1262 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Plasma proteins, Potential drug targets, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Cytosol

OverviewNCBI Gene

Aminoacyl-tRNA synthetases catalyze the aminoacylation of tRNA by their cognate amino acid. Because of their central role in linking amino acids with nucleotide triplets contained in tRNAS, aminoacyl-tRNA synthetases are thought to be among the first proteins that appeared in evolution. Isoleucine-tRNA synthetase belongs to the class-I aminoacyl-tRNA synthetase family and has been identified as a target of autoantibodies in the autoimmune disease polymyositis/dermatomyositis. Alternatively spliced transcript variants have been found. [provided by RefSeq, Nov 2012]

Canonical amino-acid sequenceUniProt

1262 residues, UniProt reviewed canonical sequence.

>P41252|IARS1
     1  MLQQVPENIN FPAEEEKILE FWTEFNCFQE CLKQSKHKPK FTFYDGPPFA TGLPHYGHIL
    61  AGTIKDIVTR YAHQSGFHVD RRFGWDCHGL PVEYEIDKTL GIRGPEDVAK MGITEYNNQC
   121  RAIVMRYSAE WKSTVSRLGR WIDFDNDYKT LYPQFMESVW WVFKQLYDKG LVYRGVKVMP
   181  FSTACNTPLS NFESHQNYKD VQDPSVFVTF PLEEDETVSL VAWTTTPWTL PSNLAVCVNP
   241  EMQYVKIKDV ARGRLLILME ARLSALYKLE SDYEILERFP GAYLKGKKYR PLFDYFLKCK
   301  ENGAFTVLVD NYVKEEEGTG VVHQAPYFGA EDYRVCMDFN IIRKDSLPVC PVDASGCFTT
   361  EVTDFAGQYV KDADKSIIRT LKEQGRLLVA TTFTHSYPFC WRSDTPLIYK AVPSWFVRVE
   421  NMVDQLLRNN DLCYWVPELV REKRFGNWLK DARDWTISRN RYWGTPIPLW VSDDFEEVVC
   481  IGSVAELEEL SGAKISDLHR ESVDHLTIPS RCGKGSLHRI SEVFDCWFES GSMPYAQVHY
   541  PFENKREFED AFPADFIAEG IDQTRGWFYT LLVLATALFG QPPFKNVIVN GLVLASDGQK
   601  MSKRKKNYPD PVSIIQKYGA DALRLYLINS PVVRAENLRF KEEGVRDVLK DVLLPWYNAY
   661  RFLIQNVLRL QKEEEIEFLY NENTVRESPN ITDRWILSFM QSLIGFFETE MAAYRLYTVV
   721  PRLVKFVDIL TNWYVRMNRR RLKGENGMED CVMALETLFS VLLSLCRLMA PYTPFLTELM
   781  YQNLKVLIDP VSVQDKDTLS IHYLMLPRVR EELIDKKTES AVSQMQSVIE LGRVIRDRKT
   841  IPIKYPLKEI VVIHQDPEAL KDIKSLEKYI IEELNVRKVT LSTDKNKYGI RLRAEPDHMV
   901  LGKRLKGAFK AVMTSIKQLS SEELEQFQKT GTIVVEGHEL HDEDIRLMYT FDQATGGTAQ
   961  FEAHSDAQAL VLLDVTPDQS MVDEGMAREV INRIQKLRKK CNLVPTDEIT VYYKAKSEGT
  1021  YLNSVIESHT EFIFTTIKAP LKPYPVSPSD KVLIQEKTQL KGSELEITLT RGSSLPGPAC
  1081  AYVNLNICAN GSEQGGVLLL ENPKGDNRLD LLKLKSVVTS IFGVKNTELA VFHDETEIQN
  1141  QTDLLSLSGK TLCVTAGSAP SLINSSSTLL CQYINLQLLN AKPQECLMGT VGTLLLENPL
  1201  GQNGLTHQGL LYEAAKVFGL RSRKLKLFLN ETQTQEITED IPVKTLNMKT VYVSVLPTTA
  1261  DF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against IARS1 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)
0.24
Highest tissue expression
50 nTPM

Expression across tissuesHPA

Tissue

  • thyroid gland: 50 nTPM
  • parathyroid gland: 45 nTPM
  • tongue: 42 nTPM
  • smooth muscle: 35 nTPM
  • skeletal muscle: 35 nTPM
  • tonsil: 31 nTPM

Single-cell type

  • erythrocyte progenitors: 249 nCPM
  • basal keratinocytes: 205 nCPM
  • epididymal principal cells: 182 nCPM
  • suprabasal keratinocytes: 165 nCPM
  • megakaryocyte-erythroid progenitors: 145 nCPM
  • podocytes: 137 nCPM

Immune cell

  • MAIT T-cell: 9.6 nTPM
  • NK-cell: 8.7 nTPM
  • memory CD8 T-cell: 7.7 nTPM
  • naive CD4 T-cell: 7.5 nTPM
  • naive CD8 T-cell: 7.3 nTPM
  • myeloid DC: 7.1 nTPM

Brain region

  • choroid plexus: 17 nTPM
  • hypothalamus: 12 nTPM
  • pons: 11 nTPM
  • medulla oblongata: 10 nTPM
  • cerebral cortex: 10 nTPM
  • basal ganglia: 9.4 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about IARS1.

Disease | AllUniProt

Conditions IARS1 is implicated in, by any mechanism.

  • Growth retardation, impaired intellectual development, hypotonia, and hepatopathy (GRIDHH) MIM:617093

Disease | GeneticClinVar

37 pathogenic / likely-pathogenic of 529 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.77
gnomAD pLI
0
DepMap mean gene effect
-1.88
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

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of IARS1 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 IARS1 as an antibody target. Whether an autoantibody or antibody against IARS1 could matter depends on whether native IARS1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

IARS1 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.

Source-annotated serology context

The source annotations explicitly mention antibody, autoantibody, autoantigen, or autoimmune context. This is biological context, not study-specific reactivity.

  • Isoleucine-tRNA synthetase belongs to the class-I aminoacyl-tRNA synthetase family and has been identified as a target of autoantibodies in the autoimmune disease polymyositis/dermatomyositis.

Canonical record: https://seroatlas.com/gene/IARS1. 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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