PFK knockdown causes a severe growth defect, but only mild changes in the metabolome.

A–Growth curves of PFK^RNAi and in Δfbp.sbp/^RNAiPFK show a severe growth defect after RNAi. Levels of PFK mRNA are shown as detected by qRT-PCR, compared to non-induced cells, and normalised to 18S, 24 h tetracycline induction (insets). B–LC-MS metabolomics in HMI-11 medium depleted of glucose, and supplemented with ¹³C₃-glycerol. The proportion of the C₁₃ label incorporation relative to the total amount is indicated. G3P –glycerol 3-phosphate, F6P –fructose 6-phosphate, F1,6bP–fructose 1,6-bisphosphate. 2T1 ¹³C –parental cell line in medium with ¹³C-glycerol, PFK^RNAi–non-induced PFK RNAi cell lines in medium with ¹³C-glycerol, PFK^RNAi + Tet–PFK RNAi induced for 24 h in medium with ¹³C-glycerol, Δfbp.sbp/PFK–non-induced Δfbp.sbp/^RNAiPFK cell line in medium with ¹³C-glycerol, Δfbp.sbp/PFK + Tet—Δfbp.sbp/^RNAiPFK cell line induced for 24 h in medium with ¹³C-glycerol. C–Same as in B), but relative changes in the total levels of metabolites are depicted. P5P –pentose 5-phosphates, O8P –octulose 8-phosphate, S7P –sedoheptulose 7-phosphate.