Size is not the sole factor dictating the sensitivity of RNP transport to reduced Lis1 levels. (A) Cross-sectional fluorescent area of RNPs containing different RNAs. Values shown are means of the mean area of RNPs per WT embryo. In A and C, n is number of embryos analyzed. Note that the values obtained are unlikely to represent the true size of RNPs due to light scattering in the embryo, but allow the relative size of RNPs formed by different species to be evaluated (no overt differences in the size of fluorescent RNPs were observed between WT and lis1 mutant genotypes, e.g., Video 4). (B) Fluorescent, nonenzymatic in situ hybridization demonstrating a reduction in the apical accumulation of endogenous h transcripts (green) in lis1^E415/lis1^k11702 cycle 14 blastoderm embryos compared with WT. Nuclei, red (DAPI). Note that h is transcribed in stripes. Bar, 10 µm. (C) Box-and-whisker plot revealing a statistically significant decrease in the apical/basal fluorescence of endogenous h signal in lis1 mutant embryos compared with WT. Whiskers mark the first and 95th percentile, box marks 50th percentile, crosses mark the maximum and minimum values, and the hollow square and horizontal line represents the mean and median, respectively. ***, P < 0.001 (unpaired t test).