Mitotic centrosomes associate with Rab11-endosomes as they reorient towards the cytokinetic bridge.(A) Time-lapse of pre-abscising human (HeLa) cell expressing DsRed-PACT (inverted grays, top panel; gray in merge, bottom panel) and GFP-FIP3 (cyan in merge, bottom panel). Video 2 Pink arrow, centrosome. Dashed lines, cell boundaries. Scale bar, 10 μm. (B) Time-lapse of a pre-abscising human (Hela) cell expressing Dendra-Rab11. Dendra-Rab11 is photoconverted from 507 nm emission (cyan in merge, bottom panel) to 573 nm emission (inverted grays, top panel; magenta in merge, bottom panel) using 405 nm light within an region of interest over the centrosome (pink arrow) at 0 min. Dashed lines, cell boundaries. Scale bar, 10 μm. (C) Violin plot with median (orange dashed line) and quartiles (black lines) depicting fold change of photoconverted Dendra-Rab11 (573 nm emission) increase at the cytokinetic bridge. Each dot in the plot represents a cell and the different colors depict separate experiments. n = 6 cells and n = 4 experiments. Two-tailed t test, ***P < 0.001. n-values and statistical results detailed in Table S1. (D) A zebrafish embryo pre-abscising cell expressing mCh-Rab11 (gray) fixed and immunolabeled for γ-tubulin (magenta) and DNA (DAPI, blue). Dashed lines, cell boundaries. Scale bar, 10 μm. Insets (d’ and d’’), 2X magnification. (E) Model depicting centrosomes (green) containing Rab11-endosomes (orange) reorienting towards the cytokinetic bridge with associated midbody (purple) during pre-abscission.
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