Fig. 3: TUG regulates the organization of the Golgi apparatus.
From: TUG protein acts through a disordered region to organize the early secretory pathway
a WT and TUG KO MEFs were immunostained to detect KDELr and GM130. Note the compacted Golgi morphology in TUG KO MEFs. b Quantification of Golgi length along the nuclear circumference. Plots show mean ± s.d.; N = 35 WT and 33 KO cells, analyzed using a two-tailed t test. c Compaction of Golgi based on GM130 images was calculated using a circularity function (see Methods). Plots show mean ± s.d.; N = 24 WT and 29 KO cells, analyzed using a two-tailed t test. d Electron microscopy (EM) tomography imaging of Golgi complexes in WT and TUG KO MEFs. At left, cross sections of TUG KO (upper) and WT (lower panels) MEFs are shown. Narrow, well-stacked cisternae are pseudo-colored in blue, dilated cisternae are salmon, and ballooned areas are marked by asterisks. At right, tomographic reconstructions of Golgi complexes in TUG KO and WT MEFs are shown. In addition to dilated cisterna, accumulated small vesicles were observed in TUG KO cells (arrows). e 4Pi-SMS side view images of Golgi stacks are shown, immunostained for GM130 (cis-Golgi; magenta) and Golgin97 (trans-Golgi; green). Images from WT and TUG KO MEFs are indicated. Shaded areas were used to quantify the separation of cis and trans markers in line scan profiles. f Line scan profiles were generated for GM130 and Golgin97. The intensity profile in each channel was fitted to a gaussian and the peak-to-peak distance was used to measure the separation between these cis and trans markers. In the example shown, this distance was 264 nm in WT MEFs and 323 nm in TUG KO MEFs; the increase in KO cells was ~60 nm. FWHM represents full width at half-maximum. g Violin plots of the shortest distances of trans points to the cis isosurface for four WT and four TUG KO cells (see Supplementary fig. 4). The median value for each cell is indicated. For WT cells, N = 254,025, 291,063, 372,879, and 252,424 measurements; for KO cells, N = 290,987, 272,770, 156,019, and 163,102 measurements. The overall median distance was 155.0 nm for WT cells and 210.2 nm for KO cells.
