neuropilin Activators

Neuropilins are a family of transmembrane glycoproteins widely expressed in various tissues, particularly in neurons, endothelial cells, and immune cells. They serve as multifunctional receptors involved in numerous biological processes, ranging from embryonic development to cancer progression. Functionally, neuropilins act as co-receptors for various ligands, including vascular endothelial growth factors (VEGFs), semaphorins, and certain members of the transforming growth factor-beta (TGF-β) superfamily. Through their interactions with these ligands, neuropilins regulate critical cellular processes such as angiogenesis, axon guidance, immune cell function, and neuronal patterning.

Activation of neuropilins is primarily mediated through ligand binding and subsequent downstream signaling events. Upon ligand binding, neuropilins form complexes with their cognate receptors, such as VEGF receptors (VEGFRs) or plexins, thereby initiating intracellular signaling cascades. For example, in angiogenesis, neuropilin-1 forms a complex with VEGFR-2, enhancing VEGF signaling and promoting endothelial cell migration, proliferation, and vessel formation. Additionally, in axon guidance, neuropilins interact with class 3 semaphorins and plexins to mediate repulsive or attractive signaling cues, guiding axonal growth and pathfinding during neuronal development. Furthermore, neuropilins can transduce signals intracellularly through their cytoplasmic domains, contributing to the regulation of cell migration, survival, and cytoskeletal dynamics. Overall, understanding the precise mechanisms of neuropilin activation provides insights into their diverse biological functions and implications in health and disease.