ID:EPHA3_HUMAN DESCRIPTION: RecName: Full=Ephrin type-A receptor 3; EC=2.7.10.1; AltName: Full=EPH-like kinase 4; Short=EK4; Short=hEK4; AltName: Full=HEK; Short=Human embryo kinase; AltName: Full=Tyrosine-protein kinase TYRO4; AltName: Full=Tyrosine-protein kinase receptor ETK1; Short=Eph-like tyrosine kinase 1; Flags: Precursor; FUNCTION: Receptor tyrosine kinase which binds promiscuously membrane-bound ephrin family ligands residing on adjacent cells, leading to contact-dependent bidirectional signaling into neighboring cells. The signaling pathway downstream of the receptor is referred to as forward signaling while the signaling pathway downstream of the ephrin ligand is referred to as reverse signaling. Highly promiscuous for ephrin-A ligands it binds preferentially EFNA5. Upon activation by EFNA5 regulates cell-cell adhesion, cytoskeletal organization and cell migration. Plays a role in cardiac cells migration and differentiation and regulates the formation of the atrioventricular canal and septum during development probably through activation by EFNA1. Involved in the retinotectal mapping of neurons. May also control the segregation but not the guidance of motor and sensory axons during neuromuscular circuit development. CATALYTIC ACTIVITY: ATP + a [protein]-L-tyrosine = ADP + a [protein]-L-tyrosine phosphate. SUBUNIT: Heterotetramer upon binding of the ligand. The heterotetramer is composed of an ephrin dimer and a receptor dimer. Oligomerization is probably required to induce biological responses. Forms a ternary EFNA5-EPHA3-ADAM10 complex mediating EFNA5 extracellular domain shedding by ADAM10 which regulates the EFNA5-EPHA3 complex internalization and function. Interacts with NCK1 (via SH2 domain); mediates EFNA5-EPHA3 signaling (By similarity). Interacts (phosphorylated) with PTPN1; dephosphorylates EPHA3 and may regulate its trafficking and function. Interacts (phosphorylated) with CRK; mediates EFNA5- EPHA3 signaling through RHOA GTPase activation. SUBCELLULAR LOCATION: Isoform 1: Cell membrane; Single-pass type I membrane protein. SUBCELLULAR LOCATION: Isoform 2: Secreted. TISSUE SPECIFICITY: Widely expressed. Highest level in placenta. PTM: Autophosphorylates upon activation by EFNA5. Phosphorylation on Tyr-602 mediates interaction with NCK1. Dephosphorylated by PTPN1. DISEASE: Defects in EPHA3 may be a cause of colorectal cancer (CRC) [MIM:114500]. SIMILARITY: Belongs to the protein kinase superfamily. Tyr protein kinase family. Ephrin receptor subfamily. SIMILARITY: Contains 1 Eph LBD (Eph ligand-binding) domain. SIMILARITY: Contains 2 fibronectin type-III domains. SIMILARITY: Contains 1 protein kinase domain. SIMILARITY: Contains 1 SAM (sterile alpha motif) domain.
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
ModBase Predicted Comparative 3D Structure on P29320
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Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.
US Server
Sequence and Links to Tools and Databases 
Common Gene Haplotype Alleles 
