Seroatlas · Human Serome Atlas

SEPSECS

O-phosphoseryl-tRNA(Sec) selenium transferase

Also known as: SecS, SLA, SLA-p35, SLA/LP, SPCS_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9HD40
Gene
SEPSECS
Ensembl
ENSG00000109618
Chromosome
4
Canonical length
501 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Vesicles
Quaternary structure
Homotetramer

OverviewNCBI Gene

The amino acid selenocysteine is the only amino acid that does not have its own tRNA synthetase. Instead, this amino acid is synthesized on its cognate tRNA in a three step process. The protein encoded by this gene catalyzes the third step in the process, the conversion of O-phosphoseryl-tRNA(Sec) to selenocysteinyl-tRNA(Sec).[provided by RefSeq, Mar 2011]

Canonical amino-acid sequenceUniProt

501 residues, UniProt reviewed canonical sequence.

>Q9HD40|SEPSECS
     1  MNRESFAAGE RLVSPAYVRQ GCEARRSHEH LIRLLLEKGK CPENGWDEST LELFLHELAI
    61  MDSNNFLGNC GVGEREGRVA SALVARRHYR FIHGIGRSGD ISAVQPKAAG SSLLNKITNS
   121  LVLDIIKLAG VHTVANCFVV PMATGMSLTL CFLTLRHKRP KAKYIIWPRI DQKSCFKSMI
   181  TAGFEPVVIE NVLEGDELRT DLKAVEAKVQ ELGPDCILCI HSTTSCFAPR VPDRLEELAV
   241  ICANYDIPHI VNNAYGVQSS KCMHLIQQGA RVGRIDAFVQ SLDKNFMVPV GGAIIAGFND
   301  SFIQEISKMY PGRASASPSL DVLITLLSLG SNGYKKLLKE RKEMFSYLSN QIKKLSEAYN
   361  ERLLHTPHNP ISLAMTLKTL DEHRDKAVTQ LGSMLFTRQV SGARVVPLGS MQTVSGYTFR
   421  GFMSHTNNYP CAYLNAASAI GMKMQDVDLF IKRLDRCLKA VRKERSKESD DNYDKTEDVD
   481  IEEMALKLDN VLLDTYQDAS S

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SEPSECS 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)
0.27
Highest tissue expression
24 nTPM

Expression across tissuesHPA

Tissue

  • liver: 24 nTPM
  • kidney: 7.7 nTPM
  • thymus: 4.8 nTPM
  • duodenum: 4.6 nTPM
  • small intestine: 4.6 nTPM
  • breast: 4 nTPM

Single-cell type

  • hepatocytes: 74 nCPM
  • tuft cells: 69 nCPM
  • early primary spermatocytes: 56 nCPM
  • proximal tubule cells: 45 nCPM
  • enterocytes: 45 nCPM
  • sertoli cells: 43 nCPM

Immune cell

  • intermediate monocyte: 0.6 nTPM
  • classical monocyte: 0.2 nTPM
  • MAIT T-cell: 0.2 nTPM
  • memory CD4 T-cell: 0.2 nTPM
  • myeloid DC: 0.2 nTPM
  • naive CD4 T-cell: 0.2 nTPM

Brain region

  • white matter: 1.8 nTPM
  • cerebral cortex: 1.7 nTPM
  • medulla oblongata: 1.4 nTPM
  • pons: 1.3 nTPM
  • thalamus: 1.3 nTPM
  • hypothalamus: 1.2 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SEPSECS.

Disease | AllUniProt

Conditions SEPSECS is implicated in, by any mechanism.

Disease | GeneticClinVar

105 pathogenic / likely-pathogenic of 680 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on SEPSECS was assayed in.

Disease | AutoantibodyPubMed

Conditions in which antibodies against SEPSECS are reported. Each links to that disease's full target list.

ReferencesPubMed · IEDB

Publications for SEPSECS from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Reference: AutoantibodyPubMed

25 publications

Show 20 more

Reference: T cellIEDB

2 publications

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. IEDB — curated epitope assays from the Immune Epitope Database (Vita et al., Nucleic Acids Research 2019). Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

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)
0.99
gnomAD pLI
0
gnomAD missense Z
0.02
DepMap mean gene effect
-0.53
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

  • tRNA binding
  • O-phosphoseryl-tRNA(Sec) selenium transferase activity

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

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

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

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