Production of very-high-amylose cassava by post-transcriptional silencing of branching enzyme genes  

作　　者：Wenzhi Zhou Shanshan Zhao Shutao He Qiuxiang Ma Xinlu Lu Xiaomeng Hao Hongxia Wang Jun Yang Peng Zhang 

机构地区：[1]National Key Laboratory of Plant Molecular Genetics,CAS Center for Excellence in Molecular Plant Sciences,Institute of Plant Physiology and Ecology,Shanghai Institutes for Biological Sciences,the Chinese Academy of Sciences,Shanghai 200032,China [2]Shanghai Key Laboratory of Plant Functional Genomics and Resources,Shanghai Chenshan Plant Science Research Center,Shanghai Chenshan Botanical Garden,the Chinese Academy of Sciences,Shanghai 201602,China [3]University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Journal of Integrative Plant Biology》2020年第6期832-846,共15页植物学报（英文版）

基　　金：the grants from the National Key R&D Program of China“Development and Regulation of Economically Important Traits in Tropical Crops(2018YFD1000500);the National Natural Science Foundation of China(31871682);the National Key Technology Research and Development Program of China(2015BAD15B01);the Collaborative Innovation Action—Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAASXTCX2016009);the Earmarked Fund for China Agriculture Research System(CARS-11-shzp)。

摘　　要：High amylose starch can be produced by plants deficient in the function of branching enzymes(BEs).Here we report the production of transgenic cassava(Manihot esculenta Crantz)with starches containing up to 50%amylose due to the constitutive expression of hair-pin ds RNAs targeting the BE1 or BE2 genes.All BE1-RNAi plant lines(BE1i)and BE2-RNAi plant lines(BE2i)were grown up in the field,but with reduced total biomass production.Considerably high amylose content in the storage roots of BE2i plant lines was achieved.Storage starch granules of BE1i and BE2i plants had similar morphology as wild type(WT),however,the size of BE1i starch granules were bigger than that of WT.Comparisons of amylograms and thermograms of all three sources of storage starches revealed dramatic changes to the pasting properties and a higher melting temperature for BE2i starches.Glucan chain length distribution analysis showed a slight increase in chains of DP>36 in BE1i lines and a dramatic increase in glucan chains between DP 10-20 and DP>40 in BE2i lines.Furthermore,BE2i starches displayed a B-type X-ray diffraction pattern instead of the A-type pattern found in BE1i and WT starches.Therefore,cassava BE1 and BE2 function differently in storage root starch biosynthesis.

关 键 词：CHAINS branching PATTERN 

分 类 号：S533[农业科学—作物学]