Viral growth factor- and STAT3 signaling-dependent elevation of the TCA cycle intermediate levels during vaccinia virus infection
Fig 3
VACV infection alters the TCA cycle-related metabolism.
(A) A decrease in Acetyl-CoA upon VACV infection in HFFs cultured in media without glutamine. The level of Acetyl-CoA at 8 hpi in the metabolic profiling of Fig 1A was shown. (B) VACV infection decreases the level of acetyl CoA in HFFs cultured in medium containing glutamine. HFFs infected with WT VACV at an MOI of 2 in media with glucose plus glutamine and the Acetyl-CoA level was measured at 8 hpi using an Acetyl-CoA assay kit. (C) A simplified overview of carnitine metabolism in β-oxidation. The long-chain fatty acids are acylated and then carnitylated by carnitine palmitoyltransferase system, which is then transported into the mitochondrial matrix for β-oxidation to fuel the TCA cycle. (D) VACV infection increases the levels of carnitine-conjugated fatty acids. The metabolic profiling data of fatty acyl carnitines in VACV-infected HFFs (Supplementary File S2) was uploaded to the MetaboAnalyst tool and then a hierarchically clustered heatmap was generated using Ward’s minimum variance and Euclidean distance measure. Color keys indicate the levels of different metabolites; blue: lowest, red: highest. The number on top of the plots represent the p-values comparing the average levels of indicated metabolites levels in mock- and VACV-infected HFFs (E) The levels of long-chain fatty acids are reduced in VACV-infected HFFs. The metabolic profiling data of long-chain fatty acids in VACV-infected HFFs (Supplementary File S2) was processed as in Fig 3D. (F) VACV infection does not affect the level of lactate. The level of lactate in HFFs infected with MOI-3 of WT-VACV in media with glucose (Glc) or glucose plus asparagine (Glc+N) at 8 hpi was determined by global metabolic profiling in Fig 1A. (G) The glycolysis intermediates are either unaffected or reduced by VACV infection. The levels of glycolysis intermediates in HFFs infected with MOI-3 of WT-VACV in medium with glucose (Glc) or glucose plus asparagine (Glc+N) at 8 hpi as determined by global metabolic profiling in Fig 1A. Error bars represent the standard deviation of at least three biological replicates. ns, P > 0.05; *, P ≤ 0.05; **, P ≤ 0.01; ***, P ≤ 0.001; ****, P ≤ 0.0001.