MTs are nucleated around the entire posterior in par-1 hypomorphic mutant oocytes, abolishing the orientation bias. Also see Videos 8 and 9. (A) Trails projected EB1-GFP image time series. Arrowheads indicate EB1 foci nucleating MTs. The dashed line distinguishes oocyte and follicle cells, and an asterisk marks the posterior. (B) Image as in A after foreground extraction, highlighting EB1 foci nucleating MTs throughout the posterior. (C) Wild-type oocyte processed as in B showing the absence of MT initiating from the posterior cortex. (D–F) Mapping MT orientation in the par-1 hypomorphic mutant: tracked EB1 trajectories, windmap, and rose diagram (refer to Fig 4 and Materials and methods for further details). A, anterior; P, posterior; N, oocyte nucleus. Bars, 15 µm.