转录组学揭示MeFtsZ2-1基因过量表达对木薯糖代谢的影响  

Transcriptomics Reveals the Effect of MeFtsZ2-1 Gene Overexpression on Cassava Sugar Metabolism

作　　者：吴坤林 黎广松 闵义[1] Wu Kunlin;Li Guangsong;Min Yi(School of Life Sciences,Hainan University,Haikou,570228)

机构地区：[1]海南大学生命科学学院,海口570228

出　　处：《分子植物育种》2022年第24期8043-8050,共8页Molecular Plant Breeding

基　　金：国家自然科学基金项目(31960039)资助。

摘　　要：为了解MeFtsZ2-1基因过量表达对木薯光合及糖代谢的影响,本研究对转基因及野生型木薯的光合酶活性及主要糖代谢产物(可溶性总糖,淀粉,蔗糖,果糖及葡萄糖)含量进行测定,并对叶片及块根进行转录组测序分析。结果表明,与野生型相比,转基因木薯PEPC和PPDK酶活性增加,而Rubisco酶活性无显著差异。转基因木薯块根可溶性总糖、蔗糖含量较野生型显著减少,而淀粉、果糖含量较野生型显著增加。基于转录组数据,在叶片中鉴定并筛选出与糖类代谢相关的9条通路,其中光合作用通路中有1个基因表达较野生型显著上调。在蔗糖/淀粉代谢通路中鉴定到17个差异表达基因,12个较野生型显著上调,5个较野生型显著下调,其中上调的基因有7个注释为β-葡萄糖苷酶。在块根中鉴定并筛选出与糖类代谢相关的11条通路。在蔗糖/淀粉代谢通路中鉴定到9个差异表达基因,其中3个较野生型显著上调,6个较野生型显著下调。转基因木薯块根中蔗糖含量减少,而淀粉含量增加可能与蔗糖磷酸合酶及蔗糖磷酸酶表达下调,颗粒结合淀粉合酶表达上调有关。这与转基因木薯块根中蔗糖含量减少,而淀粉含量增加的结果一致。该研究为质体分裂调控介导木薯品质改良研究奠定基础。In order to unders tand the effects of MeFtsZ2-1 gene overexpression on photosynthesis and glucose metabolism in cassava, the photosynthase activity and the contents of main sugar metabolites(soluble total sugar,starch, sucrose, fructose and glucose) in transgenic and wild-type cassava, were measured, and transcriptomic sequencing was performed on leaves and tuberous roots. The results showed that compared with the wild type, PEPC and PPDK enzyme activities of transgenic cassava were increased, while Rubisco enzyme activities were not significantly different. Compared with the wild type, the contents of soluble total sugar and sucrose in transgenic cassava tuberous roots decreased, while the contents of starch and fructose increased. Based on transcriptome data,nine pathways related to carbohydrate metabolism were identified and screened out in leaves, and one gene in the photosynthetic pathway was significantly up-regulated compared with the wild type. Seventeen differentially expressed genes were identified in the sucrose/starch metabolic pathway, 12 of which were significantly up-regulated and 5 were significantly down-regulated compared with the wild type, and 7 of the up-regulated genes were anno tated as β-glucosidase. Eleven pathways related to carbohydrate metabolism were identified and screened in tuberous roots. Nine differentially expressed genes were identified in the sucrose/starch metabolic pathway, of which 3 were significantly up-regulated and 6 were significantly down regulated compared with the wild type. The sucrose content in transgenic cassava tubers decreased, while the increase of starch content may be related to the down-regulation of sucrose phosphate synthase and sucrose phosphatase expression, and the up regulation of granule bound starch synthase expression. The results are consistent. This study laid a foundation for the study of cassava quality improvement mediated by plastid division.

关 键 词：木薯 MeFtsZ2-1 转基因 淀粉/蔗糖代谢 转录组学 

分 类 号：S533[农业科学—作物学]