FIGURE 4.

Identification of the key domains in JIP3 that are critical for axon elongation. A, schematic representation of the JIP3 mutants. Amino acid numbers correspond to appropriate domains within the JIP3 deletion constructs. B, HEK293 cells were transiently transfected with the indicated constructs. At 48 h after transfection, cells were lysed and immunoblotted with anti-GFP and anti-α-tubulin antibodies. C, images of representative neurons (DIV5) transfected with empty vector, JIP3-EGFP, or JIP3 mutants described in A. Cells were stained with anti-GFP (green) and anti-α-tubulin (red) antibodies. Scale bar, 40 μm. D, quantitation of axon length from the neurons shown in C; >100 cells were examined in each experiment (n = 3, *, p < 0.05; **, p < 0.01, versus the control group; Student's t test).