Methods to Study the Signal Transduction of the Surface Receptor Tyrosine Kinase TrkB in Neurons

Receptor tyrosine kinases (RTK) belong to a major class of cell surface receptors that transduce extracellular signals to elicit diverse intracellular responses. Upon binding to specific ligand, the RTKs become dimerized and autophosphorylated at tyrosine residues. This creates binding sites to recruit specific signaling intermediates and hence trigger distinct signaling events. The cellular response to a given RTK may be modified through the regulation of membrane insertion and receptor internalization. Here we use Trk receptor and its ligand, the neurotrophin brain-derived neurotrophic factor (BDNF), as an example to illustrate the approaches (coimmunoprecipitation and biotinylation) to study the surface expression and signal transduction mediated by this class of RTK in the nervous system.