Ephrin ligand (EFNA/EFNB)

Ephrin ligands are membrane-bound proteins that serve as the primary binding partners for Eph receptor tyrosine kinases, the largest subfamily of receptor tyrosine kinases [UniProt]. They are divided into two subclasses: Ephrin-A (EFNA1-5), which are anchored to the cell membrane via a glycosylphosphatidylinositol (GPI) linkage, and Ephrin-B (EFNB1-3), which are transmembrane proteins with a short cytoplasmic signaling domain [NCBI Gene]. A hallmark of ephrin-Eph interaction is bidirectional signaling, where "forward" signaling occurs in the receptor-expressing cell and "reverse" signaling occurs in the ligand-expressing cell, facilitating complex cell-cell communication [PubMed: 24104751]. These ligands are essential for embryonic development, particularly in axon guidance, angiogenesis, and the formation of tissue boundaries [Nature Reviews Cancer]. In adult tissues, dysregulation of ephrin ligands is linked to cancer progression, where they modulate tumor cell proliferation, migration, and the recruitment of blood vessels [PubMed: 21886171]. Therapeutic interventions targeting ephrins, such as the decoy receptor sEphB4-HSA, are currently being investigated in clinical trials for their ability to inhibit tumor growth and angiogenesis by disrupting ligand-receptor binding [ClinicalTrials.gov].

Other names

Eph family receptor ligandsLERK (Ligand of Eph-Related Kinase)Eph-related receptor tyrosine kinase ligandsEph-family ligands

Inhibition of ligand-receptor binding and modulation of bidirectional signaling through decoy receptors or monoclonal antibodies [PubMed: 21886171].