Impaired directionality after electroporation with the Tuba1a S140G-mutant construct. (A and B) Time-lapse video microscopy sequences for control Tuba1a (A) or S140G-mutant (B) constructs. An example of tracking for five different neurons is shown (numbered in color from one to five) within a video frame of 2 h 20 min (every 20 min) for both conditions. Rostrocaudal orientations are indicated in the first image of each sequence. Neurons migrated mainly tangentially along the RMS in the Tuba1a control condition (A), whereas with the Tuba1a S140G-mutant construct, the migration appeared less organized, showing more frequent changes of direction. (C and D) An example of the tracking of 15 neurons is shown in Tuba1a control (C) and Tuba1a S140G-mutant (D) conditions. Neurons migrated less unidirectionally after electroporation with the Tuba1a S140G-mutant construct. Bars: (A and B) 56 µm; (C and D) 26 µm.