Neuropilin 1 (NRP1)

Neuropilin is a protein receptor active in neurons.There are two forms of Neuropilins, NRP-1 and NRP-2. They are transmembrane glycoproteins, and predominantly co-receptors for another class of proteins known as Semaphorins. Of the Semaphorins, NRP-1 and NRP-2 are specifically receptors for Class-3 Semaphorins, which, amongst many things, are responsible for axon guidance during the development of the nervous system in vertebrates. Neuropilins work as co-receptors as they have a very small cytoplasmic domain and thus rely upon other molecules to transduce their signals across a cell membrane, normally Plexins. Neuropilins generally work as dimers and different combinations have different affinities for molecules. .