Fig. 2: Abnormal centrosomal and nuclear movements in MGE cells expressing PAK3 mutants. | Molecular Psychiatry

Fig. 2: Abnormal centrosomal and nuclear movements in MGE cells expressing PAK3 mutants.

From: PAK3 activation promotes the tangential to radial migration switch of cortical interneurons by increasing leading process dynamics and disrupting cell polarity

Fig. 2

A Time-lapse sequences illustrate the migration of MGE cells co-electroporated with eGFP (A1), eGFP-PAK3-ca (A2), eGFP-PAK3-kd (A3) and pericentrin-mKO1 plasmids. Pericentrin-mKO1 labels the centrosome (white in lower frames, white arrowheads). The nucleus is the oval structure at cell rear. On time-lapse sequences, we identified nuclear translocations and the forward centrosomal migration preceding each nuclear translocation. Time in hours:minutes on frames. Scale bar, 10 µm. B Histograms compare the maximal centrosomal-nuclear distance in time-lapse sequences (shown on frames with green and white arrowheads in A). Statistical significance is assessed by the One Way ANOVA test (p < 0.0001) and Bonferroni’s post-hoc tests (*p = 0.0136). Histograms compare in MGE cells expressing eGFP and PAK3 mutants, the mean migration speed of the cell body (C), the percentage of resting phases (D1) and the frequency (D2, left) and amplitude (D2, right) of nuclear translocations (Parameters defined in Fig. S1E1). Statistical significance is assessed by Kruskal–Wallis tests (all p < 0.0001) and Dunn’s post-hoc tests. E Time-lapse sequence shows the GFP signal (top row) during the migration cycle of a control MGE cell expressing the myosin 2B-GFP fusion protein. The GFP intensity is color-coded in the bottom row as indicated on scale. (See also supplementary Movie 2E). F Schemes and color-coded pictures illustrate 4 patterns of GFP repeatedly observed in the cell body of migrating MGE cells expressing myosin 2B-GFP: 1, GFP accumulation in the rostral swelling during centrosomal forward migration; 2, GFP concentration at the nuclear rear prior and during nuclear translocation; 3, GFP shift to the nuclear front after nuclear translocation (associated with gliding movement); 4, spreading of small GFP dots in the whole cell body during the resting phase. G Histogram representing the frequency of the 4 GFP patterns in MGE cells expressing RFP (black dot), RFP-PAK3-ca (red dot) and RFP-PAK3-kd (blue dot) constructs (See also representative time-lapse sequences in supplementary Fig. S2D, Movies S2D1 and S2D2). Statistical significance of distributions is assessed by chi2 tests. H Scheme summarizes the influence of the expression of PAK3 mutants on the morphology, nuclear-centrosomal distance and subcellular localization of myosin 2B in migrating INs.

Back to article page