Fig. 2.

Morphological changes induced by activated Rho GTPases is not affected by NHE1 inhibition. a. Wild type mouse neocortical neurons at 2 DIV were treated with 10 μm of lysophosphatidic acid (LPA), a well-known RhoA activator. Time course of the effect of LPA treatment on the total number of neurites. Numbers of WT neurons analyzed under each condition are shown in the columns. b. A mouse neuron showing the expression of HA-tagged NHE1. The neurites were visualized with phalloidin that binds actin. c. LPA-induced neurite retraction is neither sensitive to cariporide nor rescued by NHE1 overexpression. Representative examples of WT neurons that were either untransfected (WT) or transiently transfected with HA-tagged full-length NHE1 (NHE1) and cultured for 48 h, LPA (10 μM) and/or cariporide (1 μM) were present for 1 h before fixation. NHE1 transfected neurons were identified by anti-HA antibody. d. Quantification of neurite outgrowth in untransfected WT or NHE1-transfected neurons, in the absence or presence of LPA. **P < 0.01, ***P < 0.001