Fig. 5: RRBP1 expression in liver and primary hepatocytes in fed and fasting conditions.

A Immunoblotting and quantification analysis of RRBP1 protein in total liver lysates of indicated conditions. n = 3 in each group. B Immunostaining of RRBB1 and Glutamine synthetase (GS) in liver sections from lean mice in fed and fasted and from RRBP1 deficient mice. Left panel shows images pseudo colored by ‘Fire’ LUT. Scale bars: 100 µm. C Quantification of the immuno-stained tissue sections shown in B. For the quantification, a line was drawn from the edge of a central vein to the portal vein. The fluorescence intensity of RRBP1 and GS signals across each line was measured by plot profile and the distances were transformed into percentages. n = 9 fed, n = 7 fasted. Representative of 4 independent experiments. For C, two-way ANOVA, Sídák’s multiple comparisons test ****p < 0.0001. D Immunostaining of RRBP1 (green) and mitochondrial OXPHOS proteins (Oxphos cocktail antibody, red) in primary hepatocytes isolated from mice in fed and fasted state. Images were acquired with Lattice-SIM microscopy. Scale bars: 5 µm. E Quantification of RRBP1 fluorescence intensity in proximity with mitochondria. n = 5 cells fed and n = 7 cells fasted. Two-tailed, unpaired t test, p < 0.05. F Immunostaining of RRBP1 (green) and mitochondrial OXPHOS proteins (red) in primary hepatocytes isolated from mice in fed and fasted state. Images were acquired with STED microscopy. Scale bars: 2 µm. Representative image from 7 cells per group. G Lattice-SIM fluorescence images of primary hepatocytes isolated from lean mice in fed state exogenously expressing Adenoviurs-GFP-Sec61β (upper panel) and adenovirus-GFP-RRBP1 (lower panel), representative of three independent experiments. Scale bars: 10 µm. Mitochondria were stained with MitoTracker. For the line graph in C and bar graph in E, data are shown as mean ± s.e.m.