Supplementary Figure 5: Myosin Vb mediates the actin network dynamics and asymmetric spindle positioning.

(a) Image correlation analysis of actin network dynamics in live oocytes expressing EGFP-UtrCH to label F-actin together with mCherry-myosin-Va-tail or mCherry-myosin-Vb-tail. Each image in a time series (time interval 1.57 s) was correlated with the first image. For details see Experimental Procedures. The number of analysed oocytes is specified in italics (aggregation over 2 independent experiments). Data are mean, with error bars displaying s.d. (b) Spindle movements (magenta, EGFP-MAP4; microtubules, merged with differential interference contrast [DIC]) in live oocytes injected with control siRNA (Control) or with siRNAs targeting myosin Vb (Myosin Vb RNAi). White ovals mark initial spindle positions. Scale bar, 10 μm. (c) The spindle was tracked in oocytes in 3D data sets (11 sections, every 8 μm) as shown in (b) and spindle movements were plotted. The number of analysed oocytes is specified in italics (aggregation over 3-5 independent experiments). Data are mean, with error bars displaying s.d. (d) The efficiency of asymmetric spindle positioning in oocytes injected with control siRNA (Control) or with siRNAs targeting myosin Vb (Myosin Vb RNAi) is shown. The number of analysed oocytes is specified in italics (aggregation over 3-5 independent experiments). (e) The spindle speeds were determined from the plots in (c). The number of analysed oocytes is specified in italics (aggregation over 3-5 independent experiments). Box plot as in Fig. 1e.