(A, B) Kymographs of oskMS2-GFP mRNPs (green) associated with Khc-mKate2 (A, red) and mCherry-Tm1-I/C (B, red) ex vivo. Arrows indicate motile RNPs in stable complex with Khc (A) or Tm1-I/C (B), the arrowheads point to non-motile oskMS2-RNPs showing no obvious accumulation of the tagged protein. Note that mCherry-Tm1-I was exposed twice as long as Khc-mKate to obtain comparable red fluorescence signals. Scale bars represent 1 µm and 1 second, respectively.(C-E) Relative Khc-mKate2 (C), mCherry-Tm1-I/C (D) coverage of motile (white) and non-motile (grey) oskMS2-GFP trajectories. Numbers within the boxes indicate the number of trajectories and the number of ooplasms (in brackets) analysed. Percentages above the plots show the fraction of RNPs that were found stably and reliably associating with the indicated protein (for at least half of the duration of the trajectory, p<0.01, binominal distribution, see also Fig EV2B). P values of pairwise Mann-Whitney U tests are indicated above the boxplots. 