Seroatlas · Human Serome Atlas

RTCB

RNA-splicing ligase RtcB homolog

Also known as: C22orf28, FAAP, HSPC117, RTCB_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9Y3I0
Gene
RTCB
Ensembl
ENSG00000100220
Chromosome
22
Canonical length
505 aa
Protein class
Enzymes, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Vesicles,Cytosol

OverviewNCBI Gene

Enables RNA ligase (GTP) activity and vinculin binding activity. Involved in tRNA splicing, via endonucleolytic cleavage and ligation. Located in cytosol and nucleoplasm. Part of tRNA-splicing ligase complex. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

505 residues, UniProt reviewed canonical sequence.

>Q9Y3I0|RTCB
     1  MSRSYNDELQ FLEKINKNCW RIKKGFVPNM QVEGVFYVND ALEKLMFEEL RNACRGGGVG
    61  GFLPAMKQIG NVAALPGIVH RSIGLPDVHS GYGFAIGNMA AFDMNDPEAV VSPGGVGFDI
   121  NCGVRLLRTN LDESDVQPVK EQLAQAMFDH IPVGVGSKGV IPMNAKDLEE ALEMGVDWSL
   181  REGYAWAEDK EHCEEYGRML QADPNKVSAR AKKRGLPQLG TLGAGNHYAE IQVVDEIFNE
   241  YAAKKMGIDH KGQVCVMIHS GSRGLGHQVA TDALVAMEKA MKRDKIIVND RQLACARIAS
   301  PEGQDYLKGM AAAGNYAWVN RSSMTFLTRQ AFAKVFNTTP DDLDLHVIYD VSHNIAKVEQ
   361  HVVDGKERTL LVHRKGSTRA FPPHHPLIAV DYQLTGQPVL IGGTMGTCSY VLTGTEQGMT
   421  ETFGTTCHGA GRALSRAKSR RNLDFQDVLD KLADMGIAIR VASPKLVMEE APESYKNVTD
   481  VVNTCHDAGI SKKAIKLRPI AVIKG

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against RTCB 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)
0.19
Highest tissue expression
88 nTPM

Expression across tissuesHPA

Tissue

  • duodenum: 88 nTPM
  • tonsil: 82 nTPM
  • small intestine: 75 nTPM
  • skin: 74 nTPM
  • kidney: 71 nTPM
  • liver: 70 nTPM

Single-cell type

  • enterocytes: 234 nCPM
  • suprabasal keratinocytes: 167 nCPM
  • cytotrophoblasts: 156 nCPM
  • esophageal apical cells: 147 nCPM
  • syncytiotrophoblasts: 139 nCPM
  • migrating cytotrophoblasts: 132 nCPM

Immune cell

  • myeloid DC: 162 nTPM
  • total PBMC: 156 nTPM
  • intermediate monocyte: 151 nTPM
  • naive B-cell: 151 nTPM
  • memory B-cell: 144 nTPM
  • classical monocyte: 136 nTPM

Brain region

  • white matter: 44 nTPM
  • pons: 42 nTPM
  • spinal cord: 39 nTPM
  • hypothalamus: 39 nTPM
  • cerebellum: 37 nTPM
  • midbrain: 37 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)
0.58
gnomAD pLI
0.01
gnomAD missense Z
1.57
DepMap mean gene effect
-0.6
DepMap dependency class
common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% 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

  • RNA-splicing ligase, RtcB
  • RNA-splicing ligase RtcB homologue, eukaryotic
  • tRNA-splicing ligase RtcB-like superfamily
  • tRNA-splicing ligase RtcB

KeywordsUniProt

InteractionsUniProt · HPA

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

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

Canonical record: https://seroatlas.com/gene/RTCB. 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).

© 2026 · Seroatlas, Discover Oregon LLC · Terms of use

Loading the interactive Seroatlas protein explorer...