Insights into triterpene synthesis and unsaturated fatty-acid accumulation provided by chromosomallevel genome analysis of Akebia trifoliata subsp . australis  

作　　者：Hui Huang Juan Liang Qi Tan Linfeng Ou Xiaolin Li Caihong Zhong Huilin Huang Ian Max Moller Xianjin Wu Songquan Song 

机构地区：[1]Key Lab oratory of Resea rch and Utilizati on of Eth nomedic inal Pla nt Reso ur ces of Hunan Province,College of Biological and Food Engineering,Huaihua University,Huaihua 418000,China [2]Kunming Institute of Botany,Chinese Academy of Scie nces,Kunming 650201,China [3]State Key Lab oratory Br eed ing Base of Dao-di Herbs,National Resource Center for Chinese Materia Medica,China Academy of Chinese Medical Science,Beijing 100700,China [4]Department of Molecular Biology and Genetics,Aarhus University,Flakkebjerg,DK-4200 Slagelse,Denmark [5]Institute of Botany,Chinese Academy of Sciences,Beijing 100093,China

出　　处：《Horticulture Research》2021年第1期419-433,共15页园艺研究（英文）

基　　金：the Natural Science Foundation of Hunan Province(2019JJ50475);Key Scientific Research Projects of Hunan Education Department(18A448);Foundation of Hunan Double First-rate Discipline Construction Pr ojects of Bioengineering and Key Lab oratory of Resea rch and Utilizati on of Ethnomedicinal Plant Resources of Hunan Province,and the National Science Foundation(81874334).

摘　　要：Akebia trifoliata subsp.australis is a well-known medicinal and potential woody oil plant in China.The limited genetic information available for A.trifoliata subsp.australis has hindered its exploitation.Here,a high-quality chromosomelevel genome sequence of A.trifoliata subsp.australis is reported.The de novo genome assembly of 682.14 Mb was generated with a scaffold N50 of 43.11 Mb.The genome includes 25,598 protein-coding genes,and 71.18%(485.55 Mb)of the assembled sequences were identi fi ed as repetitive sequences.An ongoing massive burst of long terminal repeat(LTR)insertions,which occurred~1.0 million years ago,has contributed a large proportion of LTRs in the genome of A.trifoliata subsp.australis.Phylogenetic analysis shows that A.trifoliata subsp.australis is closely related to Aquilegia coerulea and forms a clade with Papaver somniferum and Nelumbo nucifera,which supports the well-established hypothesis of a close relationship between basal eudicot species.The expansion of UDP-glucoronosyl and UDP-glucosyl transferase gene families and fi-amyrin synthase-like genes and the exclusive contraction of terpene synthase gene families may be responsible for the abundant oleanane-type triterpenoids in A.trifoliata subsp.australis.Furthermore,the acyl-ACP desaturase gene family,including 12 stearoyl-acyl-carrier protein desaturase(SAD)genes,has expanded exclusively.A combined transcriptome and fatty-acid analysis of seeds at fi ve developmental stages revealed that homologs of SADs,acyl-lipid desaturase omega fatty acid desaturases(FADs),and oleosins were highly expressed,consistent with the rapid increase in the content of fatty acids,especially unsaturated fatty acids.The genomic sequences of A.trifoliata subsp.australis will be a valuable resource for comparative genomic analyses and molecular breeding.

关 键 词：analysis saturated expanded 

分 类 号：Q943.2[生物学—植物学]