Fig. 2
From: Role of MDH2 pathogenic variant in pheochromocytoma and paraganglioma patients
MDH2 activity measured in MDH2 KD cells transfected with different vectors containing the variant of unknown significance (VUS) in MDH2. a Enzymatic activities at saturating concentrations of malate (25 mM) and NAD+ (2 mM) in p.R104G (p.Arg104Gly), p.Q130R (p.Gln130Arg), p.V160M (p.Val160Met), and p.S3F (p.Ser3Phe) variants, plus C (p.K301R-p.Lys301Arg) which is a polymorphism with minor allele frequency of 0.037, knockdown (KD) and wild-type (WT) as controls, are expressed as mean (nmol/min/mg) ± SD of 3 paired independent experiments in quadruplicate. Different shadings indicate the only variants tested in experiments in c–f. b Enzymatic activities at saturating concentrations of cells cotransfected with WT, empty vector (EV), and/or p.R104G plasmids expressed as mean of fold-change over activity in cells cotransfected with WT and EV (control) ± SD of 2 paired independent experiments at least in quadruplicate; µg of plasmid DNA transfected for each condition are showed in the figure. c–f Enzymatic activities in p.A256T, p.V160M, p.R104G, and control (p.K301R) expressed as mean of fold-change over control ± SD of at least 2 paired independent experiments in triplicate. Assays performed with reduced concentrations of malate or NAD+: c 5-fold reduction malate (5 mM), d 10-fold reduction malate (2.5 mM), e 4-fold reduction of NAD+ (0.5 mM), and f 20-fold reduction of NAD+ (0.1 mM). *****p < 0.0001, ****p< 0.001, ***p < 0.01, **p < 0.03, and *p < 0.05 based on a two-sided Mann–Whitney U test
