Loss of SORLA impairs vesicular trafficking of TrkB.

<p>(<b>A</b>) Movement of TrkB-EGFP in neurites of cultured hippocampal neurons. Arrows indicate anterograde (red) and retrograde movement (yellow), or no movement (blue) of vesicles. Images were captured every 2 sec. (<b>B</b>) The cumulative distance travelled by TrkB-EGFP fusion proteins either anterogradely or retrogradely is significantly reduced in <i>Sorl1^−/−</i> neurons as compared to controls (n = 14–16, Student’s <i>t</i>-test). (<b>C</b>) The cumulative anterograde or retrograde speed of the TrkB-EGFP fusion protein is significantly reduced in <i>Sorl1^−/−</i> neurons as compared to <i>Sorl1^+/+</i> cells (n = 14–16, Student’s <i>t</i>-test).