EFNB3s

EFNB3 proteins, also known as ephrin-B3, are members of the ephrin-B family of membrane-bound ligands that interact with EphB receptors on adjacent cells. In humans, the EFNB3 gene encodes the ephrin-B3 ligand, which is conserved across vertebrates.

Ephrin-B3 proteins are type I transmembrane glycoproteins with an extracellular ephrin domain that binds Eph receptors and a cytoplasmic tail that participates in intracellular signaling through PDZ-binding motifs.

EFNB3 mediates bidirectional signaling. Forward signaling occurs when EphB receptors are engaged by ephrin-B3, activating receptor-tyrosine kinase pathways. Reverse signaling can be triggered in EFNB3-expressing cells, influencing cytoskeletal dynamics, cell adhesion, and gene expression.

In development, EFNB3 contributes to neural circuit formation, axon pathfinding, and synapse establishment. Expression is detected in the developing central nervous system, including brain and spinal cord, with broader expression in some tissues depending on species.

Research has explored EFNB3 roles in vertebrate nervous system patterning and connectivity. While specific disease associations are still being clarified, EFNB3 signaling is considered an important component of ephrin-Eph signaling networks underlying neural development.