Seroatlas · Human Serome Atlas

NSUN3

tRNA (cytosine(34)-C(5))-methyltransferase, mitochondrial

Also known as: FLJ22609, NSUN3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9H649
Gene
NSUN3
Ensembl
ENSG00000178694
Chromosome
3
Canonical length
340 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins

OverviewNCBI Gene

Enables tRNA (cytidine-5-)-methyltransferase activity. Involved in regulation of mitochondrial translation and tRNA wobble base cytosine methylation. Located in mitochondrial matrix. Implicated in combined oxidative phosphorylation deficiency 48. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

340 residues, UniProt reviewed canonical sequence.

>Q9H649|NSUN3
     1  MLTQLKAKSE GKLAKQICKV VLDHFEKQYS KELGDAWNTV REILTSPSCW QYAVLLNRFN
    61  YPFELEKDLH LKGYHTLSQG SLPNYPKSVK CYLSRTPGRI PSERHQIGNL KKYYLLNAAS
   121  LLPVLALELR DGEKVLDLCA APGGKSIALL QCACPGYLHC NEYDSLRLRW LRQTLESFIP
   181  QPLINVIKVS ELDGRKMGDA QPEMFDKVLV DAPCSNDRSW LFSSDSQKAS CRISQRRNLP
   241  LLQIELLRSA IKALRPGGIL VYSTCTLSKA ENQDVISEIL NSHGNIMPMD IKGIARTCSH
   301  DFTFAPTGQE CGLLVIPDKG KAWGPMYVAK LKKSWSTGKW

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against NSUN3 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)
0.26
Highest tissue expression
3.7 nTPM

Expression across tissuesHPA

Tissue

  • rectum: 3.7 nTPM
  • bone marrow: 3.5 nTPM
  • colon: 3.3 nTPM
  • spleen: 3.3 nTPM
  • retina: 3.1 nTPM
  • skin: 3.1 nTPM

Single-cell type

  • sertoli cells: 143 nCPM
  • early spermatids: 133 nCPM
  • neutrophils: 69 nCPM
  • microglia: 68 nCPM
  • bergmann glia: 59 nCPM
  • oligodendrocyte progenitor cells: 59 nCPM

Immune cell

  • basophil: 5.5 nTPM
  • neutrophil: 3.3 nTPM
  • non-classical monocyte: 3 nTPM
  • NK-cell: 2.9 nTPM
  • naive CD8 T-cell: 2.5 nTPM
  • MAIT T-cell: 2.3 nTPM

Brain region

  • cerebral cortex: 12 nTPM
  • basal ganglia: 12 nTPM
  • cerebellum: 12 nTPM
  • white matter: 11 nTPM
  • amygdala: 10 nTPM
  • hypothalamus: 10 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about NSUN3.

Disease | AllUniProt

Conditions NSUN3 is implicated in, by any mechanism.

  • Combined oxidative phosphorylation deficiency 48 (COXPD48) MIM:619012

Disease | GeneticClinVar

5 pathogenic / likely-pathogenic of 143 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)
1.29
gnomAD pLI
0
gnomAD missense Z
0.31
DepMap mean gene effect
-0.04
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 8% 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 NSUN3 as an antibody target. Whether an autoantibody or antibody against NSUN3 could matter depends on whether native NSUN3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

NSUN3 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 NSUN3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/NSUN3. 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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