Fig. 7.

Tyrosine residues are required for NGF-elicited dendritic complexity. Sindbis virus infection was performed on 4-day cultured hippocampal neurons. Twenty-four hours later, medium was changed to neurobasal medium containing 2% B27 supplement and 0.5 mM l-glutamine for 12 h. Neurons overexpressing each of the four TrkA/TrkB fusion protein variants, along with GFP, were treated with NGF (100 ng/ml) for 3 days and fixed for imaging. a Sample images of hippocampal neurons expressing the indicated construct. GFP-labeled dendritic branches were imaged using a confocal microscope. b Summary of quantitative analysis of dendritic growth. Dendritic complexity was quantitated as described in Fig. 2. *Significant difference from A/B-wild group as determined by t test, *P < 0.05. n = 20 independent neurons in each group. Results are representative of at least three independent experiments. Scale bar, 20 μm