TPXL-1 recruits Aurora A^AIR-1 to astral microtubules but is not required for astral microtubule growth or nucleation. (A) Confocal images of embryos expressing TPXL-1^WT::NG (n = 10) after depletion of endogenous TPXL-1. (B) Projections of images acquired every 400 ms over a 4-s interval in embryos expressing EBP-2::GFP. Representative images are shown for a control embryo (n = 10) and for myosin-depleted hcp-4(RNAi) (n = 10), hcp-4 tpxl-1(RNAi) (n = 8), and rga-3/4(RNAi) (n = 10) embryos. To visualize EBP-2::GFP on microtubule tips without saturating the aster centers, a gamma of 1.2 was introduced in Photoshop. EBP-2 foci were counted in kymographs made along arcs 9 µm away from the anterior centrosome (yellow) and along the anterior cortex (blue) generated for the entire 1-min movie (255–315 s). (C and D) Graphs plot the mean number of EBP-2::GFP foci crossing the arcs 9 µm away from the anterior centrosome (C) and beneath the anterior cortex (D) as a percentage of the mean number in controls. Error bars are the SD; p-values are two-tailed Student’s t test (***, P < 0.001); n = number of embryos. (E) Microtubule growth rates measured 255–315 s after NEBD. Error bars are the SD; N = number of microtubules tracked in four or more embryos per condition. (F) Representative images of GFP::Aurora A^AIR in control (n = 14), tpxl-1(RNAi) (n = 10), and myosin-depleted hcp-4 tpxl-1(RNAi) (n = 11) embryos. To visualize TPXL-1^WT::NG and GFP::Aurora A^AIR on astral microtubules without saturating the aster centers, gammas of 2.5 and 2.0 were introduced in Photoshop for the images in A and F, which were scaled equivalently across conditions. Bars, 5 µm.