Fig. 1. Drosophila ROD and ZW10 protein localization. Drosophila ROD and ZW10 proteins colocalize throughout mitosis. (a-d) Wild-type larval brains were fixed and stained to detect ROD (red), ZW10 (green) and DNA (blue). (a) Prometaphase cell; (b) metaphase; (c) early anaphase; (d) late anaphase. The superimposition of ROD and ZW10 signals is shown in the merged images of each set. ROD and ZW10 are found together on prometaphase kinetochores, on the spindle fibers in metaphase, and on kinetochores of the segregating chromatids in anaphase. ROD fails to localize in a zw10 mutant background (e,f). Larval brains from zw10 mutants were fixed and stained to detect ROD (red) and DNA (blue). (e) Metaphase zw10 cell with chromosomes at the equator. (f) Anaphase zw10 cell. No discrete ROD staining can be seen in either cell. By western blot, ROD is still present in zw10 mutant brains at normal levels (data not shown). ROD localization is dependent on tension (g). In metaphase I spermatocytes, ROD distribution differs on bivalent (bi-oriented) and on univalent (mono-oriented) chromosomes. (left) DNA; (center) merged image with DNA in blue and ROD in red; (right) same image with tubulin in green. Spindle fibers stain with ROD only on kMTs attached to bi-oriented bivalents. The attached-4 univalent chromosome (arrow) shows no staining of kMTs, but has a prominent ROD signal on the presumptive kinetochore. Bars, 5 µm.
