EphA4 Protein, Human (Active, sf9, His-GST)

The EphA4 protein is a receptor tyrosine kinase that interacts with membrane-bound ephrin ligands on adjacent cells, enabling bidirectional signaling. It can be activated by both GPI-anchored ephrin-A and transmembrane ephrin-B ligands, such as EFNA1 and EFNB3. Activation of EphA4 modulates cell morphology and integrin-dependent cell adhesion by regulating the activity of Rac, Rap, and Rho GTPases. In the nervous system, EphA4 plays a crucial role in axonal guidance, including corticospinal projections and segregation of motor and sensory axons during neuromuscular circuit development. It also contributes to synaptic plasticity and is involved in repair after injury, preventing axonal regeneration. EphA4's promiscuity allows it to participate in various cell-cell signaling processes, including the development of the thymic epithelium. Furthermore, it regulates pillar cell separation in the cochlear organ of Corti by forming a complex with ADAM10 and CADH1, leading to the disruption of adherens junctions. EphA4 phosphorylates CAPRIN1, promoting the formation of a membraneless compartment.