Fig. 3.

Lamin A variants interfere with centrosome orientation and nuclear movement in Lmna^−/− MEFs and in human fibroblasts. (A) Images of LPA-stimulated Lmna^−/− MEFs expressing lamin A variants and stained for the expressed lamin A (red) and microtubules (green). The wound edge is located toward the top, and arrows indicate the centrosome. (Scale bar, 10 μm.) (B) Nucleus (red) and centrosome (blue) positions in the cells described in A. The centrosome orientation (percentage of cells) is located below the histogram. Error bars are SEM for >50 cells from at least three independent experiments. Nuclear position in E358K-expressing cells is significantly different from that in WT-expressing cells (P < 0.01) but not from that in nonexpressing controls. Nuclear position in R482W0-expressing cells is significantly different from that in nonexpressing controls (P < 0.01) but not from that in WT-expressing cells. The position of the centrosome in R482W-expressing cells is significantly different from that in each of the other conditions (P < 0.05). (C) Images of human fibroblasts from an unaffected control and from an individual with EDMD caused by the R453W LMNA mutation stimulated with LPA and stained for nuclei (blue), β-catenin and pericentrin (red), and microtubules (green). Arrows indicate the centrosome, and the wound edge is located at the top. (Scale bar, 10 μm.) (D) Nucleus (red) and centrosome (blue) positions for the cells described in C. Centrosome orientation (percentage of cells) is located below the histogram. Error bars are SEM for >100 cells from at least three independent experiments. Nucleus position and centrosome orientation in R453W are significantly different from those in control (P < 0.01).