title: Cytokinin-Regulated Sucrose Metabolism in Stay-Green Wheat Phenotype.
abstract: A wheat stay-green mutant, tasg1, was observed to exhibit significantly delayed senescence in the late developmental stage. The photosynthetic capacity of the flag leaf was greater in tasg1 than in wild type (WT) plants. In addition, the grain volume of tasg1 was significantly higher than that of WT at the early filling stage. The content of various cytokinins (CKs) in the grain was significantly higher in tasg1 than in WT and was accompanied by an upregulated expression of some cell cycle-related genes. Examination of the metabolism of soluble sugars in tasg1 and WT revealed that the concentrations of glucose (Glu), fructose (Fru), and sucrose (Suc) were higher in the flag leaves and grains of tasg1 than in WT plants. The activities of sucrose-phosphate synthase (SPS), sucrose synthase (SuSy), and cell wall invertase (CW-invertase) were higher in tasg1, suggesting an altered metabolism and transport of soluble sugars. Furthermore, when tasg1 was treated with the CK inhibitor lovastatin, the activity of invertase was inhibited and was associated with premature senescence phenotype. However, the activity of invertase was partially recovered in tasg1 when treated with 6-benzylaminopurine (BAP). The trend of change in the concentrations of Glu, Fru, and Suc was similar to that of invertase. Our results suggest that CKs might regulate the stay-green phenotype of tasg1 by regulating the invertase activity involved in Suc remobilization.
authors: State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China.
authors: Wenqiang
authors: W
authors: Wang
authors: State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China.
authors: Qunqun
authors: Q
authors: Hao
authors: College of Life Science and Technology, Nanyang Normal University, Nanyang, Henan, 473061, China.
authors: Fengxia
authors: F
authors: Tian
authors: State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China.
authors: Qinxue
authors: Q
authors: Li
authors: State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China.
authors: Wei
authors: W
authors: Wang
mesh_terms: D002453:Cell Cycle; D003583:Cytokinins / Q000235:genetics / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D009154:Mutation; D010641:Phenotype; D010940:Plant Proteins / Q000096:biosynthesis* / Q000235:genetics; D013395:Sucrose / Q000378:metabolism*; D014908:Triticum / Q000235:genetics / Q000378:metabolism*
chemical_list: D003583:Cytokinins; D010940:Plant Proteins; D013395:Sucrose