Q9GJR5 · HCST_PIG
- ProteinHematopoietic cell signal transducer
- GeneHCST
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids
- Protein existenceEvidence at protein level
- Annotation score4/5
Function
function
Transmembrane adapter protein which associates with KLRK1 to form an activation receptor KLRK1-HCST in lymphoid and myeloid cells; this receptor plays a major role in triggering cytotoxicity against target cells expressing cell surface ligands such as MHC class I chain-related MICA and MICB, and UL16-binding proteins (ULBPs); these ligands are up-regulated by stress conditions and pathological state such as viral infection and tumor transformation. Functions as a docking site for PI3-kinase PIK3R1 and GRB2. Interaction of ULBPs with KLRK1-HCST triggers calcium mobilization and activation of the PIK3R1, MAP2K/ERK, and JAK2/STAT5 signaling pathways. Both PIK3R1 and GRB2 are required for full KLRK1-HCST-mediated activation and ultimate killing of target cells. In NK cells, KLRK1-HCST signaling directly induces cytotoxicity and enhances cytokine production initiated via DAP12/TYROBP-associated receptors. In T-cells, it provides primarily costimulation for TCR-induced signals. KLRK1-HCST receptor plays a role in immune surveillance against tumors and is required for cytolysis of tumors cells; indeed, melanoma cells that do not express KLRK1 ligands escape from immune surveillance mediated by NK cells (By similarity).
GO annotations
all annotations | all molecular function | virus receptor activity | dna binding | rna binding | cytoskeletal motor activity | catalytic activity | gtpase activity | structural molecule activity | transporter activity | cytoskeletal protein binding | lipid binding | cyclase activity | antioxidant activity | oxidoreductase activity | transferase activity | hydrolase activity | lyase activity | isomerase activity | ligase activity | protein tag activity | cargo receptor activity | histone binding | protein folding chaperone | translation regulator activity | nutrient reservoir activity | receptor ligand activity | molecular transducer activity | molecular adaptor activity | toxin activity | cell adhesion mediator activity | molecular function regulator activity | virus coreceptor activity | catalytic activity, acting on a protein | catalytic activity, acting on dna | catalytic activity, acting on rna | molecular carrier activity | transcription regulator activity | general transcription initiation factor activity | molecular sensor activity | molecular sequestering activity | atp-dependent activity | other molecular function | all biological process | mitotic cell cycle | cytokinesis | cytoplasmic translation | immune system process | muscle system process | circulatory system process | renal system process | respiratory system process | carbohydrate metabolic process | generation of precursor metabolites and energy | dna replication | dna repair | dna recombination | chromatin organization | dna-templated transcription | regulation of dna-templated transcription | trna metabolic process | protein folding | protein glycosylation | amino acid metabolic process | modified amino acid metabolic process | lipid metabolic process | vitamin metabolic process | sulfur compound metabolic process | intracellular protein transport | nucleocytoplasmic transport | autophagy | inflammatory response | mitochondrion organization | cytoskeleton organization | microtubule-based movement | peroxisome organization | lysosome organization | chromosome segregation | cell adhesion | establishment or maintenance of cell polarity | programmed cell death | photosynthesis | mrna metabolic process | snrna metabolic process | vesicle-mediated transport | reproductive process | digestive system process | signaling | cell differentiation | protein catabolic process | extracellular matrix organization | regulatory ncrna-mediated gene silencing | telomere organization | cell junction organization | wound healing | ribosome biogenesis | cilium organization | anatomical structure development | cell motility | nervous system process | endocrine process | protein maturation | transmembrane transport | nucleobase-containing small molecule metabolic process | hepaticobiliary system process | membrane organization | protein-containing complex assembly | cell wall organization or biogenesis | nitrogen cycle metabolic process | protein localization to plasma membrane | defense response to other organism | detoxification | meiotic nuclear division | mitotic nuclear division | mitochondrial gene expression | carbohydrate derivative metabolic process | other biological process | all cellular component | nuclear chromosome | extracellular region | extracellular space | cell wall | nucleus | nuclear envelope | nucleoplasm | chromosome | nucleolus | mitochondrion | lysosome | endosome | vacuole | peroxisome | endoplasmic reticulum | golgi apparatus | lipid droplet | microtubule organizing center | cytosol | ribosome | cytoskeleton | plasma membrane | cilium | plastid | thylakoid | external encapsulating structure | extracellular matrix | cytoplasmic vesicle | organelle | other cellular component | |||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Aspect | Term | |
---|---|---|
Cellular Component | cell surface | |
Cellular Component | membrane | |
Molecular Function | phosphatidylinositol 3-kinase binding | |
Molecular Function | signaling receptor binding | |
Biological Process | positive regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction | |
Biological Process | regulation of immune response |
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameHematopoietic cell signal transducer
- Alternative names
Gene names
Organism names
- Organism
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Laurasiatheria > Artiodactyla > Suina > Suidae > Sus
Accessions
- Primary accessionQ9GJR5
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Membrane ; Single-pass type I membrane protein
Features
Showing features for topological domain, transmembrane.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Topological domain | 19-35 | Extracellular | |||
Transmembrane | 36-56 | Helical | |||
Topological domain | 57-79 | Cytoplasmic | |||
Keywords
- Cellular component
PTM/Processing
Features
Showing features for signal, chain, modified residue.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Signal | 1-18 | ||||
Chain | PRO_0000330292 | 19-79 | Hematopoietic cell signal transducer | ||
Modified residue | 72 | Phosphotyrosine | |||
Post-translational modification
Phosphorylated; PIK3R1 and GRB2 associate specifically with tyrosine-phosphorylated HCST.
O-glycosylated.
Keywords
- PTM
Proteomic databases
Expression
Tissue specificity
Expressed predominantly in lymphohematopoietic tissues.
Interaction
Subunit
Homodimer; Disulfide-linked. Heterohexamer composed of four subunits of HCST/DAP10 and two subunits of KLRK1. Interacts (via transmembrane domain) with KLRK1 (via transmembrane domain); the interaction is required for KLRK1 NK cell surface and induces NK cell-mediated cytotoxicity. Interacts with PIK3R1 and GRB2. Interacts with CLEC5A. Forms an CLEC5A/TYROBP/HCST trimolecular complex depending almost solely on TYROBP (By similarity).
Interacts with KLRK1. Interacts with CD300H (By similarity).
Interacts with KLRK1. Interacts with CD300H (By similarity).
Protein-protein interaction databases
Structure
Family & Domains
Sequence
- Sequence statusComplete
- Sequence processingThe displayed sequence is further processed into a mature form.
- Length79
- Mass (Da)7,930
- Last updated2001-03-01 v1
- MD5 Checksum5A1E31E390489F324D08156F3BFC5A40
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AF285444 EMBL· GenBank· DDBJ | AAG29422.1 EMBL· GenBank· DDBJ | mRNA | ||
AF285445 EMBL· GenBank· DDBJ | AAG29423.1 EMBL· GenBank· DDBJ | mRNA | ||
AF285446 EMBL· GenBank· DDBJ | AAG29424.1 EMBL· GenBank· DDBJ | Genomic DNA |