Ephrin-A1/EFNA1 Protein, Mouse (HEK293, His)

The Ephrin-A1/EFNA1 protein, a cell surface GPI-bound ligand for Eph receptors, serves a pivotal role in migration, repulsion, and adhesion during neuronal, vascular, and epithelial development. It binds promiscuously to Eph receptors on adjacent cells, instigating contact-dependent bidirectional signaling. Crucial in angiogenesis and tumor neovascularization, EFNA1-induced RAC1 GTPase activation and vascular endothelial cell migration depend on the recruitment of VAV2, VAV3, and the PI3-kinase p85 subunit by phosphorylated EPHA2. Notably, EFNA1 exerts anti-oncogenic effects by activating and down-regulating EPHA2 through induced tyrosine phosphorylation, leading to internalization and degradation. In gliomas, it acts as a negative regulator, down-regulating EPHA2 and FAK and thus playing a role in suppressing tumorigenesis. EFNA1 can induce the collapse of embryonic neuronal growth cones and regulate dendritic spine morphogenesis. Existing as both a monomer and homodimer, it forms heterodimers with EPHA2 and binds to a spectrum of receptor tyrosine kinases including EPHA1, EPHA3, EPHA4, EPHA5, EPHA6, and EPHA7.