Characterization of Rab5a-positive structures. (A) Co-motility of Rpl25-GFP (Rpl25; green in merged image) and the endosomal GTPase mCherry-Rab5a (Rab5a; red in merged image). Ribosomes localize on the bidirectionally moving Rab5a-positive structures. Brightness, contrast, and gamma settings were adjusted. See Video 5. (B) Localization of the endocytic marker FM4-64 at 1 min and 6 min after a pulse and subsequent wash-out. The dye first appears in the plasma membrane (1 min) and concentrates in GFP-Rab5a structures (green) at 6 min. Images are contrast-inverted, and brightness, contrast, and gamma settings were adjusted. (C) Co-motility of Rab5a and a fusion protein of GFP and the PX domain of Yup1 (aa 4–148). Images were contrast-inverted and adjusted with brightness, contrast, and gamma settings. Arrowheads indicate three sets of trajectories. Bars, 2 s and 1 µm. (D) Nearest neighbor tree of Rab4-, Rab5-, and Rab7-GTPases from U. maydis (red) human (green), and budding yeast (blue). Note the absence of Rab4 in yeast. (E) Co-motility of GFP-Rab4 and mCherry-Rab5a. Images were contrast-inverted, and brightness, contrast, and gamma settings were adjusted. (F and G) Colocalization of GFP-Rab7 and mCherry-Rab5a. The late endosome marker Rab7 does not localize to the rapidly moving Rab5a structures. Occasionally, largely immobile Rab7-positive late endosomes carry Rab5a (arrowheads in G). Images were contrast-inverted, and brightness, contrast, and gamma settings were adjusted.