Effect of overexpression of oilseed rapetrehalose-6-phosphate synthesis gene BnaC02.TPS8 in Arabidopsis

Trehalose-6-phosphate (T6P) serves as a pivotal signaling molecule, sensing sucrose availability and carbon metabolism. However, the mechanisms governing the regulation of T6P synthase (TPS) genes responsible for anthocyanin accumulation under conditions of low N and high sucrose remain elusive. In a previous study, we demonstrated the positive impact of a cytoplasm-localized class II TPS protein ‘BnaC02.TPS8’ on photosynthesis and seed yield improvement in Brassica napus. Ectopic overexpression of BnaC02.TPS8 in Arabidopsis seedlings resulted in elevated shoot T6P levels under N-sufficient conditions, as well as an increased carbon-to-nitrogen (C/N) ratio, sucrose accumulation, and starch storage under low N conditions. Overexpression of BnaC02.TPS8 in Arabidopsis heightened sensitivity to low N stress and high sucrose levels, accompanied by increased anthocyanin accumulation and upregulation of genes involved in flavonoid biosynthesis and regulation. To identify the pathways regulated by TPS8, we conducted transcriptome analysis of the 35S: BnaC02.TPS8-O2 lines and WT plants under N sufficient conditions using RNA-Seq.