https://nova.newcastle.edu.au/vital/access/ /manager/Index en-au 5 Variation in the promoter of the sorbitol dehydrogenase gene MdSDH2 affects binding of the transcription factor MdABI3 and alters fructose content in apple fruit https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46246 Wed 28 Feb 2024 14:48:47 AEDT ]]> MdERDL6-mediated glucose efflux to the cytosol promotes sugar accumulation in the vacuole through up-regulating TSTs in apple and tomato https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:39306 +/sugar antiporters MdTST1 and MdTST2. Overexpression of MdERDL6-1 unexpectedly increased not only glucose (Glc) concentration but also that of fructose (Fru) and sucrose (Suc) in transgenic apple and tomato leaves and fruits. RNA sequencing (RNA-seq) and expression analyses showed an up-regulation of TST1 and TST2 in the transgenic apple and tomato lines overexpressing MdERDL6-1. Further studies established that the increased sugar concentration in the transgenic lines correlated with up-regulation of TST1 and TST2 expression. Suppression or knockout of SlTST1 and SlTST2 in the MdERDL6-1–overexpressed tomato background reduced or abolished the positive effect of MdERDL6-1 on sugar accumulation, respectively. The findings demonstrate a regulation of TST1 and TST2 by MdERDL6-1, in which Glc exported by MdERDL6-1 from vacuole up-regulates TST1 and TST2 to import sugars from cytosol to vacuole for accumulation to high concentrations. The results provide insight into the regulatory mechanism of sugar accumulation in vacuoles mediated by the coordinated action of two classes of tonoplast sugar transporters.]]> Wed 10 Aug 2022 11:02:07 AEST ]]>