The GABA-modulated energy metabolism reconfiguration positively regulates cotton (Gossypium hirsutum L.) responses during post-waterlogging recovery

Plant response to waterlogging is well studied, but the understanding of plant responses during post-waterlogging recovery remains limited. In this study, we show that the waterlogging-sensitive (Z4847) and waterlogging-tolerant (ZM9001) cotton varieties have different rates of post-waterlogging recovery that correlate with waterlogging tolerance. The performance of a comparative transcriptome and metabolome analysis of the roots from two cotton varieties during recovery processes indicated the significant inhibition of the abundance of genes and metabolites related to energy metabolism in both varieties during post-waterlogging. The results also showed that the waterlogging tolerant ZM9001 plants maintained the higher carbon flows from glycolysis to the first reaction of the TCA cycle, leading to more energy production and restoring root activity during recovery processes. The interaction analysis of KEGG pathways in ZM9001 vs. Z4847 comparison during post-waterlogging displayed an extremely significant correlation between GABA metabolism and the glycolysis-citrate cycle. Therefore, we combined both multi-omics and physiological approaches and showed that the induced elevation of the GABA levels in the ZM9001 plants during recovery processes is essential in restoring its root function by generating more energy through the activation of the GABA shunt pathway. Consistent with this, the loss of GABA synthesis showed increased sensitivity to post-waterlogging, which was partially rescued by the exogenous application of GABA. Subsequently, elevated GABA levels could also provide better redox homeostasis by enhancing the antioxidant enzyme system during post-waterlogging recovery. Therefore, these findings indicate that the energy metabolism reconfiguration via re-activating GABA shunt participates in seedling survival after waterlogging stress, shedding light Overall design: The waterlogging tolerant cotton variety ZM9001 and the flood-sensitive cotton variety Z4847 at the four-leaf stage were treated Do not take 96 h of darkness for 0 h (control group in the flooding stage, DN-0), and 96 h of dark flooding for 0 h (flooding). The stage treatment group, DW-0), the dark 96 h re-light for 24 h (the recovery phase control group, DN-24), and the dark flooding for 96 h Transcriptome sequencing analysis was performed on the roots of cotton seedlings after 24 h of dehydration and re-light (recovery stage treatment group, DW-24).