Fig. 8: Giantin is necessary for clustering Golgi units.
From: Dynamic movement of the Golgi unit and its glycosylation enzyme zones
a Scattered Golgi units imaged by Airyscan in 2D in giantin knockout cells (middle) are reassembled by expressing mNeonGreen-giantin (right). The rim of the unit is stained by TMF1 in black. Nu: nucleus. Bar, 5 µm. b A graph showing the rescue experiment. The number of units per cluster of the Golgi is shown. Number of cells: 6 (shLuciferase), 7 (shGiantin), 8 (shGiantin+mNeonGreen-giantin). Number of units: 25 (shLuciferase), 16 (shGiantin), 63 (shGiantin+mNeonGreen-giantin). P values are depicted in the graph. Boxes represent 25% and 75% quartiles, lines within the box represent the median, and whiskers represent the minimum and maximum values within 1.5 x the interquartile range. The statistical significance was determined by the two tailed unpaired t-test. P values are depicted above the plots in the graph. c Representative images of shLuciferase- and shGiantin-treated cells by Airyscan in 2D. GALNT6 KI (upper panels) and XYLT2 KI (lower panels) Caco2 cells are stained with TMF1 (green) and GALNT6 (magenta) (upper panels) or with TMF1 (green) and XYLT2 (magenta) (lower panels). In the right lower panel, arrows and arrowheads indicate the Golgi units that contain very low and high amounts of XYLT2, respectively. In a and c, images are representative of at least three independent biological replicates. Bar, 5 µm. d Effects of giantin knockdown on the distribution of signal intensity of glycosylation enzymes per Golgi unit in Caco2 cells. The distribution of signal intensity is shown by variance of signals in each cell in Supplementary Fig. 10. The statistical significance of the variance was determined by the two tailed unpaired t-test. P values are depicted in the graph. e Giantin knockdown Caco2 cells display reduced amount of GAG (heparan sulphate) trapped within the cells. Lentivirus encoding two different shRNA (#2 and 3) are used for giantin knockdown. Number of samples: 3 (shLuciferase), 3 (shGiantin #2), 3 (shGiantin #3). The statistical significance was determined by the two tailed unpaired t-test. P values are depicted above the plots in the graph. Error bars represent SD.
