Seroatlas · Human Serome Atlas

LY9

T-lymphocyte surface antigen Ly-9

Also known as: CD229, hly9, LY9_HUMAN, mLY9, SLAMF3

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

Protein identityUniProt · HPA

UniProt accession
Q9HBG7
Gene
LY9
Ensembl
ENSG00000122224
Chromosome
1
Canonical length
655 aa
Protein class
CD markers, Predicted membrane proteins, Predicted secreted proteins
Subcellular location
Plasma membrane,Centriolar satellite
Secretome location
Secreted - unknown location

OverviewNCBI Gene

LY9 belongs to the SLAM family of immunomodulatory receptors (see SLAMF1; MIM 603492) and interacts with the adaptor molecule SAP (SH2D1A; MIM 300490) (Graham et al., 2006 [PubMed 16365421]).[supplied by OMIM, Mar 2008]

Canonical amino-acid sequenceUniProt

655 residues, UniProt reviewed canonical sequence.

>Q9HBG7|LY9
     1  MVAPKSHTDD WAPGPFSSKP QRSQLQIFSS VLQTSLLFLL MGLRASGKDS APTVVSGILG
    61  GSVTLPLNIS VDTEIENVIW IGPKNALAFA RPKENVTIMV KSYLGRLDIT KWSYSLCISN
   121  LTLNDAGSYK AQINQRNFEV TTEEEFTLFV YEQLQEPQVT MKSVKVSENF SCNITLMCSV
   181  KGAEKSVLYS WTPREPHASE SNGGSILTVS RTPCDPDLPY ICTAQNPVSQ RSSLPVHVGQ
   241  FCTDPGASRG GTTGETVVGV LGEPVTLPLA LPACRDTEKV VWLFNTSIIS KEREEAATAD
   301  PLIKSRDPYK NRVWVSSQDC SLKISQLKIE DAGPYHAYVC SEASSVTSMT HVTLLIYRRL
   361  RKPKITWSLR HSEDGICRIS LTCSVEDGGN TVMYTWTPLQ KEAVVSQGES HLNVSWRSSE
   421  NHPNLTCTAS NPVSRSSHQF LSENICSGPE RNTKLWIGLF LMVCLLCVGI FSWCIWKRKG
   481  RCSVPAFCSS QAEAPADTPE PTAGHTLYSV LSQGYEKLDT PLRPARQQPT PTSDSSSDSN
   541  LTTEEDEDRP EVHKPISGRY EVFDQVTQEG AGHDPAPEGQ ADYDPVTPYV TEVESVVGEN
   601  TMYAQVFNLQ GKTPVSQKEE SSATIYCSIR KPQVVPPPQQ NDLEIPESPT YENFT

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against LY9 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)
0.48
Highest tissue expression
29 nTPM

Expression across tissuesHPA

Tissue

  • tonsil: 29 nTPM
  • lymph node: 28 nTPM
  • spleen: 26 nTPM
  • thymus: 24 nTPM
  • appendix: 13 nTPM
  • small intestine: 11 nTPM

Single-cell type

  • b-cells: 425 nCPM
  • plasma cells: 124 nCPM
  • pdcs: 103 nCPM
  • t-cells: 74 nCPM
  • nk-cells: 53 nCPM
  • cdc: 48 nCPM

Immune cell

  • MAIT T-cell: 114 nTPM
  • gdT-cell: 113 nTPM
  • naive CD8 T-cell: 113 nTPM
  • naive CD4 T-cell: 110 nTPM
  • memory CD8 T-cell: 110 nTPM
  • memory CD4 T-cell: 98 nTPM

Brain region

  • medulla oblongata: 0.4 nTPM
  • spinal cord: 0.4 nTPM
  • basal ganglia: 0.3 nTPM
  • cerebral cortex: 0.3 nTPM
  • choroid plexus: 0.3 nTPM
  • pons: 0.3 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)
1.11
gnomAD pLI
0
gnomAD missense Z
-0.22
DepMap mean gene effect
-0.1
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of LY9 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 LY9 as an antibody target. Whether an autoantibody or antibody against LY9 could matter depends on whether native LY9 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

LY9 is annotated at the cell surface, where native LY9 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 LY9 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/LY9. 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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