Ip NY et al. (Neuron. 1993) discussed all of the Trks display similar dose responses to their "preferred" ligands in neuronal as compared with nonneuronal cells (i.e., NGF for TrkA, BDNF and NT-4/5 for TrkB, and NT-3 for TrkC), providing evidence against a role for accessory molecules expressed in neurons in generating receptors that would allow for responses to lower concentrations of the neurotrophins. Lamballe et al. (1991) demonstrated that gp145(trkC) is a receptor for NTF3, a factor important in the development of certain areas of the central nervous system, but does not bind NGF or BDNF.