Fig. 6: OGT supresses lipolysis by modulating PLIN1 O-GlcNAcylation and phosphorylation.
From: O-GlcNAc transferase inhibits visceral fat lipolysis and promotes diet-induced obesity
a IP and Western blot analysis showing the effects of OGT on PLIN1 O-GlcNAcylation and phosphorylation; p-Ser antibody recognizes proteins phosphorylated on serine residues; cells were treated with IBMX/Fsk before analysis. b IP and Western blot analysis showing the effects of OGT knockout on endogenous PLIN1 O-GlcNAcylation and phosphorylation; hollow arrowheads indicate IgG heavy chains. c IP and Western blot analysis showing that OGT overexpression attenuates IBMX/Fsk-induced PLIN1 phosphorylation at serine 517. d IBMX/Fsk-induced lipolysis measured by glycerol release (n = 3/group). e IBMX/Fsk-induced lipolysis measured by glycerol released from cells transfected with HA-PLIN1 (WT), HA-PLIN1-AA (AA), and HA-PLIN1-EE (EE) (n = 6–11/group). f Basal and IBMX/Fsk-induced lipolysis measured by glycerol released from cells transfected with Myc or Myc-OGT together with HA, HA-PLIN1, HA-PLIN1-AA, or HA-PLIN1-EE (n = 4/group). g Immunofluorescence images of cells transfected with HA-PLIN1, HA-PLIN1-AA, or HA-PLIN1-EE, cultured in 0.4 mM oleic acid, treated with or without IBMX/Fsk, and stained with antibody against HA (Red), BODIPY 493/503 (green), and DAPI (blue); scale bar is 10 μm. h, i Mean average and cumulative frequency distribution of lipid droplet size shown in g (n > 150/group). j Immunofluorescence images of primary adipocytes differentiated from WT and OGT AKO eWAT SVFs; adipocytes were treated with IBMX/Fsk, fixed, and stained with antibody against CGI-58 (red), BODIPY 493/503 (green), and DAPI (blue), scale bar is 20 μm. k IP and Western blot analysis showing the interaction between endogenous CGI-58 and ATGL in eWAT of 6 h fasted WT and OGT AKO mice; hollow arrowheads indicate IgG heavy chains. l IBMX/Fsk-induced lipolysis measured by glycerol released from primary adipocytes differentiated from WT and OGT AKO eWAT SVFs (n = 4 for Atglistatin-treated WT, six for other groups); Atglistatin (10 μM) was used to inhibit ATGL activity. Data are presented as mean ± s.e.m. Statistical analysis: Student’s t test for i and ANOVA with Dunnett multiple comparisons for the rest, *p < 0.05, **p < 0.01, and ***p < 0.001; n.s., not significant. Source data are provided as a Source Data file.
