A reference-grade genome assembly for Astragalus mongholicus and insights into the biosynthesis and high accumulation of triterpenoids and flavonoids in its roots  

作　　者：Yi Chen Ting Fang He Su Sifei Duan Ruirui Ma Ping Wang Lin Wu Wenbin Sun Qichen Hu Meixia Zhao Lianjun Sun Xuehui Dong 

机构地区：[1]College of Agronomy and Biotechnology,China Agricultural University,Beijing 100193,China [2]The Second Clinical Medical College of Guangzhou University of Chinese Medicine,Guangdong Provincial Hospital of Traditional Chinese Medicine,Guangzhou 510120,China [3]Department of Microbiology and Cell Science,Institute of Food and Agricultural Sciences,University of Florida,Gainesville,FL 32611,USA

出　　处：《Plant Communications》2023年第2期193-213,共21页植物通讯（英文）

基　　金：supported by grants from the City-University Cooperation Project of China(201904710111639).

摘　　要：Astragalus membranaceus var.mongholicus(AMM),a member of the Leguminosae,is one of the most important medicinal plants worldwide.The dried roots of AMM have a wide range of pharmacological effects and are a traditional Chinese medicine.Here,we report the first chromosome-level reference genome of AMM,comprising nine pseudochromosomes with a total size of 1.47 Gb and 27868 protein-encoding genes.Comparative genomic analysis reveals that AMM has not experienced an independent wholegenome duplication(WGD)event after the WGD event shared by the Papilionoideae species.Analysis of long terminal repeat retrotransposons suggests a recent burst of these elements at approximately 0.13 million years ago,which may explain the large size of the AMM genome.Multiple gene families involved in the biosynthesis of triterpenoids and flavonoids were expanded,and our data indicate that tandemduplication has been the main driver for expansion of these families.Among the expanded families,the phenylalanine ammonia-lyase gene family was primarily expressed in the roots of AMM,suggesting their roles in the biosynthesis of phenylpropanoid compounds.The functional versatility of 2,3-oxidosqualene cyclase genes in cluster Ⅲ may play a critical role in the diversification of triterpenoids in AMM.Our findings provide novel insights into triterpenoid and flavonoid biosynthesis and can facilitate future research on the genetics and medical applications of AMM.

关 键 词：Astragalus membranaceus var.mongholicus genome sequences LTR-RTs TRITERPENOID flavonoid 

分 类 号：O62[理学—有机化学]