GAP activity of SNX26 is attributed to its effect on dendritic spine formation.
A, cultured hippocampal neurons were co-transfected at DIV 13 with GFP-SNX26 or GFP-R350I and mCherry and fixed at DIV 14. Scale bar, 15 μm. B–E, quantification of the number of total protrusions, spines, and filopodia with expression of SNX26 or R350I. Spines were defined as dendritic protrusions of <5 μm in length with heads and filopodia as dendritic protrusions of <10 μm in length without heads. Data were collected from 20 to 24 dendrites of 15–16 neurons for each group in three independent experiments. ***, p < 0.001 (Student's t test).