Fig. 4: One-Carbon metabolism is activated to support autoinflammation in RRP1 knock-out macrophages.
From: The RNA-binding protein RRP1 brakes macrophage one-carbon metabolism to suppress autoinflammation
a Heatmap of 1C-metabolites in wild-type (WT) and RRP1 KO RAW 264.7 cells upon IL-1β induction for 12 h. Color indicates normalized intensities (z-score). b ELISA detection of SAM, methionine (Met), THF levels in RRP1 KO RAW 264.7 cells after over-expressing the Flag tagged full-length RRP1 (FL), Nop52 and C-terminal (Cter) followed by IL-1β stimulation for 8 h. The RRP1 KO cells transfected with empty Vector were used as controls. c Ratio of intracellular serine (M + 3) uptake from exogenous L-serine-[13C3], out of the total serine pools in WT and RRP1 KO RAW 264.7 cells upon IL-1β induction for 4 h or not. The ratio is show as Mass Distribution Vector (MDV). d Abundance of intracellular SAM total pools in WT and RRP1 KO RAW 264.7 cells upon IL-1β induction for 4 h or not. The ratio is show as Mole Percentage Enrichment (MPE). Ratio of intracellular SAM (M + 3) (e), methionine (M + 1- M + 3) (f), methionine (M + 4) (g) derived from L-serine-[13C3], out of their respective total pools in WT and RRP1 KO RAW 264.7 cells upon IL-1β induction for 4 h or not. The ratio is show as MDV. h Schematic of L-serine-[13C3] labeling patterns. i–l RT-qPCR quantification of Il-1b, Il6 mRNAs in WT or RRP1 KO RAW 264.7 cells stimulated with IL-1β for indicated hours in medium replenishment with exogenous SAM, methionine (Met) and serine. ELISA, Isotope Tracers and RT-qPCR data are presented as means ± SD of (b, i–l, n = 3; c–g, n = 4) biologically replicates from more than two independent experiments with student’s t test (two-tailed unpaired). Source data are provided as a Source Data file.
