Figure 6. Metabolic profiling indicates reduced flux through central metabolic pathways and the folate cycle in rpl22aΔ cells.

(A) Eleven metabolites shown at the bottom had significantly reduced levels in rpl22aΔ cells (Log2FC ≥ 1, p<0.05; based on bootstrapped ANOVA; see Materials and methods) and they were significantly enriched for the metabolic pathways shown to the right (FDR < 0.05). Pathway enrichment analysis was done with the MetaboAnalyst R language package. The metabolites were identified with untargeted, MS-based profiling of primary metabolites and biogenic amines, and targeted amino acid analysis. Metabolites indicated with gray in the Table are part of the pathways shown to the right. (B) The Log2-transformed peak intensities from the MS-based profiling of the metabolites shown in A (except Glycine) are on the y-axis. The strains used in the analysis are on the x-axis. (C) The Log2-transformed levels (in nmoles) of amino acids, after PTH-derivatization, Edman degradation and HPLC detection, are shown on the y-axis. The red arrows indicate the only amino acids (Gly and Trp) whose levels were significantly lower in rpl22aΔ cells (Log2FC ≥ 1, p<0.05; based on bootstrapped ANOVA; see Materials and Methods). The strains used in the analysis are on the x-axis, and they were in the BY4742 background.

Figure 6—figure supplement 1. Exogenous addition of metabolites from pathways affected in rpl22aΔ cells does not suppress the slower growth of these cells.

Cultures from the indicated strains shown to the left (in the diploid BY4743 background in A and B; in the haploid BY4742 background in C), were spotted onto solid plates with standard undefined media (YPD; see Materials and Methods. In each case, aliquots from saturated cultures were spotted in 10-fold serial dilutions. The plates contained the compounds shown on top in each case (GSH is reduced glutathione and GSSG is oxidized glutathione), at the indicated concentrations. The plates were photographed after they were incubated for 3 days at 30°C.

Figure 6—figure supplement 2. Nobiletin is accumulated in rpl22aΔ cells.

(A) Structure of nobiletin. (B) Peak intensities assigned to nobiletin from mass spectrometry are on the y-axis. The strains used in the analysis are on the x-axis, and they were in the BY4742 background.