Seroatlas · Human Serome Atlas

KLRD1

Natural killer cells antigen CD94

Also known as: CD94, KLRD1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q13241
Gene
KLRD1
Ensembl
ENSG00000134539
Chromosome
12
Canonical length
179 aa
Protein class
CD markers, Predicted intracellular proteins, Predicted membrane proteins

OverviewNCBI Gene

Natural killer (NK) cells are a distinct lineage of lymphocytes that mediate cytotoxic activity and secrete cytokines upon immune stimulation. Several genes of the C-type lectin superfamily, including members of the NKG2 family, are expressed by NK cells and may be involved in the regulation of NK cell function. KLRD1 (CD94) is an antigen preferentially expressed on NK cells and is classified as a type II membrane protein because it has an external C terminus. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2017]

Canonical amino-acid sequenceUniProt

179 residues, UniProt reviewed canonical sequence.

>Q13241|KLRD1
     1  MAVFKTTLWR LISGTLGIIC LSLMSTLGIL LKNSFTKLSI EPAFTPGPNI ELQKDSDCCS
    61  CQEKWVGYRC NCYFISSEQK TWNESRHLCA SQKSSLLQLQ NTDELDFMSS SQQFYWIGLS
   121  YSEEHTAWLW ENGSALSQYL FPSFETFNTK NCIAYNPNGN ALDESCEDKN RYICKQQLI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KLRD1 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
Cell surface
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.39
Highest tissue expression
16 nTPM

Expression across tissuesHPA

Tissue

  • spleen: 16 nTPM
  • bone marrow: 9.7 nTPM
  • lymph node: 6.8 nTPM
  • pituitary gland: 4.8 nTPM
  • liver: 4.7 nTPM
  • lung: 4.7 nTPM

Single-cell type

  • nk-cells: 1,053 nCPM
  • t-cells: 298 nCPM
  • neutrophils: 147 nCPM
  • choroid plexus epithelial cells: 134 nCPM
  • innate lymphoid cells: 87 nCPM
  • distal convoluted tubule cells: 85 nCPM

Immune cell

  • NK-cell: 738 nTPM
  • gdT-cell: 513 nTPM
  • naive CD8 T-cell: 220 nTPM
  • memory CD8 T-cell: 218 nTPM
  • total PBMC: 163 nTPM
  • MAIT T-cell: 58 nTPM

Brain region

  • cerebellum: 27 nTPM
  • cerebral cortex: 26 nTPM
  • white matter: 25 nTPM
  • basal ganglia: 24 nTPM
  • hippocampal formation: 24 nTPM
  • amygdala: 23 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)
1.21
gnomAD pLI
0
gnomAD missense Z
0.43
DepMap mean gene effect
0.09
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

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of KLRD1 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 KLRD1 as an antibody target. Whether an autoantibody or antibody against KLRD1 could matter depends on whether native KLRD1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KLRD1 is annotated at the cell surface, where native KLRD1 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label KLRD1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KLRD1. 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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