MePHD1.2 affects the synthesis of cyanogenic glycosides by regulating transcription of MeCYP79D2 in cassava  

作　　者：Mengtao Li Xiao Zhao Yajun Li Yuanchao Li Xiaoye Zhao Weitao Mai Luqman Khan Qibing Liang Qingchun Yin Wenquan Wang Jinping Liu Xin Chen 

机构地区：[1]Institute of Tropical Agriculture and Forestry,Hainan University,Haikou,570228,National Key Laboratory for Tropical Crop Breeding,Sanya 572025,Hainan,China [2]Institute of Tropical Bioscience and Biotechnology,Chinese Academy of Tropical Agricultural Sciences,Haikou 571101,Hainan,China [3]College of Plant Science and Technology,Huazhong Agricultural University,Wuhan 430070,Hubei,China [4]State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/College of Life Science and Technology,Guangxi University,Nanning 530004,Guangxi,China [5]Haikou Branch of Hainan Food and Drug Inspection Institute,Haikou 570311,Hainan,China [6]Hainan Institute for Food Control,Key Laboratory of Tropical Fruits and Vegetables Quality and Safety for State Market Regulation,Haikou 570314,Hainan,China [7]Sanya Research Institute,Chinese Academy of Tropical Agricultural Sciences,Sanya 572025,Hainan,China

出　　处：《The Crop Journal》2025年第1期204-214,共11页作物学报(英文版)

基　　金：supported by grants from the National Natural Science Foundation of China(32460505);China Agriculture Research System(CARS-11);the Chinese Academy of Tropical Agricultural Sciences for the Science and Technology Innovation Team of the National Tropical Agricultural Science Center(CATASCXTD202301);Additional support was provided by the Hainan Province Graduate Innovation Research Project(Hyb2020-09);the Key Laboratory of Tropical Fruits and Vegetables Quality and Safety for State Market Regulation(KF-2023016).

摘　　要：The high content of cyanogenic glycosides(CG)in cassava tubers affects food safety.CG are involved in the plant growth and development and protect cassava leaves from herbivorous predators.However,the regulatory mechanism of CG biosynthesis remains poorly understood.Here,yeast one-hybrid assays were performed using a mixed cDNA library of cassava tubers and leaves as prey and the promoter of MeCYP79D2 as bait.MeCYP79D2,a cytochrome P450 protein,is the rate-limiting enzyme for CG synthesis in cassava.From this information,a candidate regulator of MeCYP79D2 was selected and identified as transcription factor MePHD1.2.MePHD1.2,located in the nucleus and exhibiting an inhibitory transcription activity directly bound to an AT-rich motif in the promoter of MeCYP79D2.In cassava,the transcriptional activity of MeCYP79D2 was considerably enhanced in mephd1.2 mutant lines leading to increased linamarin and lotaustralin contents.Deletion of MePHD1.2 promoted the production of CGs in cassava and decreased transcription inhibition on MeCYP79D2,exposing a novel regulatory module governing biosynthesis of CGs.

关 键 词：Cyanogenic glycosides Cytochrome P450 Manihot esculenta MePHD1.2 

分 类 号：S533[农业科学—作物学]