Localization of ALK5 in Rab11+ recycling endosomes is beclin 1-dependent. Representative images of neurons infected with (a) ctrl shRNA or (b) bec shRNA and stained with antibodies against ALK5 (pseudocolored green) and Rab11 (pseudocolored red). Regions in the box were brightened to ease visualization and enlarged below. Intensity traces (white offset lines) from the original image are plotted at right. Red arrowheads indicate ALK5 puncta that don’t colocalize with Rab11. c Quantification of the fraction of ALK5 colocalizing with Rab11 in cells infected with ctrl or bec shRNA, expressed as the colocalization coefficient. Data are combined results of three independent experiments (n = 27 fields/group). Planned comparison of colocalization coefficients in control and beclin 1 shRNA cells were analyzed by unpaired Student’s t-test, ***p ≤ 0.001. Bar graphs are mean ± SEM.