EPHA3

This gene belongs to the ephrin receptor subfamily of the protein-tyrosine kinase family. EPH and EPH-related receptors have been implicated in mediating developmental events, particularly in the nervous system. Receptors in the EPH subfamily typically have a single kinase domain and an extracellular region containing a Cys-rich domain and 2 fibronectin type III repeats. The ephrin receptors are divided into 2 groups based on the similarity of their extracellular domain sequences and their affinities for binding ephrin-A and ephrin-B ligands. This gene encodes a protein that binds ephrin-A ligands. Two alternatively spliced transcript variants have been described for this gene. [provided by RefSeq, Jul 2008]

EPH Receptor A3

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.

Axon guidance Source: GO_Central
Cell adhesion Source: UniProtKB-KW
Cell migration Source: UniProtKB
Cellular response to retinoic acid Source: BHF-UCL
Ephrin receptor signaling pathway Source: UniProtKB
Fasciculation of motor neuron axon Source: UniProtKB
Fasciculation of sensory neuron axon Source: UniProtKB
Negative regulation of endocytosis Source: UniProtKB
Peptidyl-tyrosine phosphorylation Source: UniProtKB
Positive regulation of kinase activity Source: GO_Central
Positive regulation of neuron projection development Source: BHF-UCL
Positive regulation of protein localization to plasma membrane Source: UniProtKB
Regulation of actin cytoskeleton organization Source: UniProtKB
Regulation of epithelial to mesenchymal transition Source: UniProtKB
Regulation of focal adhesion assembly Source: UniProtKB
Regulation of GTPase activity Source: UniProtKB
Regulation of microtubule cytoskeleton organization Source: UniProtKB
Transmembrane receptor protein tyrosine kinase signaling pathway Source: GO_Central

Isoform 1: Cell membrane
Isoform 2: Secreted

Colorectal cancer (CRC):
A complex disease characterized by malignant lesions arising from the inner wall of the large intestine (the colon) and the rectum. Genetic alterations are often associated with progression from premalignant lesion (adenoma) to invasive adenocarcinoma. Risk factors for cancer of the colon and rectum include colon polyps, long-standing ulcerative colitis, and genetic family history.

Extracellular: 21-541
Helical: 542-565
Cytoplasmic: 566-983

Autophosphorylates upon activation by EFNA5. Phosphorylation on Tyr-602 mediates interaction with NCK1. Dephosphorylated by PTPN1.