Fig. 6: De novo amino acid biosynthesis is affected in the wild-type and the re-6 mutant after Citr treatment.
From: RETICULATA1 is a plastid-localized basic amino acid transporter
a,b, The percentage of unlabelled and labelled Orn (a) and Gln (b). Metabolites were extracted from the green tissue of 14-day-old seedlings, 2 days after labelling with 4 mM 15NH4Cl with (orange triangles) or without (black circles) 5 mM Citr. Data are shown as four biological replicates. Asterisks indicate statistically significant differences (*P < 0.05; ***P < 0.001; two-sided Student’s t-test). Exact P values (a and b) are shown in the Source data with 95% confidence intervals. c,d, Schematic depiction of the impact of Citr treatment on de novo biosynthesis in the re-6 mutant (c) and the wild type (d). The slightly reduced biosynthesis of Orn in the wild type—due to feedback inhibition in its biosynthetic pathway (red line) caused by the accumulation of Orn (red arrow), which results from the partial inhibition of RE1 (white circle) and RER1 (grey circle) transport activity by excess Citr (orange triangles)—is indicated by a reduced line thickness. In the re-6 mutant, Orn biosynthesis is almost completely blocked due to a feedback inhibition in its biosynthetic pathway (red line) caused by an accumulation of Orn (red arrow) as a result of a knockout of RE1 (white circle with red cross) and an inhibition of RER1 (grey circle) transport activity by excess Citr (orange triangles).
