[Research progresses on signal transduction of neurotrophins].

Binding of neurotrophins and their receptors lead to dimerization and autophosphorylation of trks. Activated trkA initiates the Ras pathway and finally opens the transcriptions of immediate early genes and delayed response genes or participates directly in physiological responses. Target-derived neurotrophins bind to and induce phosphorylation of trk receptors at the axonal terminal. Active trk or NT-trk or other signal molecules can be retrogradely transported along the axon to transduct messages to neuronal nucleus. There are local autocrine and paracrine mechanisms besides target-derived NTs. Following nervous system injury, increased gene expressions of NTs and their receptors and increased retrograde axonal transport are helpful to survive and regenerate for injured neurons. Lacking NTs and their receptors will result in serious abnormal development of nervous system of mice.