Extended Data Fig. 8: TUG regulates mitochondrial function and morphology and has no large effect on muscle fiber type.

a, WT and MTKO soleus muscles from mice that had been fed a HFD for 2.5 weeks were imaged using electron microscopy. Lipid droplets were noted in MTKO muscles, but not WT muscles, and were adjacent to mitochondria, as shown. b–e, Images of soleus muscles from HFD-fed WT and MTKO mice (N=3 each) were obtained by electron microscopy and were analyzed to quantify mitochondrial density (b), area (c), length (d), and width (e). Mitochondria were traced manually on 5-9 images from each mouse. Each data point represents the average of the measurements from a single image. N=22 WT and 21 MTKO images were quantified. Data are presented as mean ±SEM and analyzed using two-tailed t-tests. f, Relative abundances of the indicated transcripts in quadriceps muscles were measured using qPCR. N=4 WT, 5 MTKO, and 4 UBX mice. Data are plotted as mean ±SEM and pairwise analyses were done using two-tailed t-tests. g, Cross-sections of quadriceps muscles were stained to detect myosin heavy chain type IIA using immunohistochemistry. h, The percentage of muscle fibers that stained for MHC type IIA was quantified from 2-3 images from each of 5 separate mice of each genotype. N=12 WT, 12 MTKO, and 14 UBX images were quantified, and data are plotted as mean ±SEM.