Neurotrophin-3 is a neurotrophic factor in the NGF (Nerve Growth Factor) family of neurotrophins. Neurotrophin-3 is a protein growth factor which has activity on certain neurons of the peripheral and central nervous system: it helps to support the survival and differentiation of e, Xenopus/Amphibian,isting neurons, and encourages the growth and differentiation of new neurons and synapses. Mice born without the ability to make NT-3 have loss of proprioceptive and subsets of mechanoreceptive sensory neurons.