The neurotrophins are a small group of dimeric proteins that profoundly affect the
development of the nervous system of vertebrates. Recent studies have established clear
correlations between the survival requirements for different neurotrophins of functionally
distinct subsets of sensory neurons. The biological role of the neurotrophins is not limited to
the prevention of programmed cell death of specific groups of neurons during development.
Neurotrophin-3 in particular seems to act on neurons well before the period of target …