A reference-grade genome of the xerophyte Ammopiptanthus mongolicus sheds light on its evolution history in legumes and droughttolerance mechanisms  

作　　者：Lei Feng Fei Teng Na Li Jia-Cheng Zhang Bian-Jiang Zhang Sau-Na Tsai Xiu-Le Yue Li-Fei Gu Guang-Hua Meng Tian-Quan Deng Suk-Wah Tong Chun-Ming Wang Yan Li Wei Shi Yong-Lun Zeng Yue-Ming Jiang Weichang Yu Sai-Ming Ngai Li-Zhe An Hon-Ming Lam Jun-Xian He 

机构地区：[1]School of Life Sciences and State Key Laboratory of Agrobiotechnology,The Chinese University of Hong Kong,Sha Tin,New Territories,Hong Kong,China [2]Guangdong Provincial Key Laboratory of Biotechnology for Plant Development,School of Life Sciences,South China Normal University,Guangzhou 510631,China [3]BGI-Shenzhen Tech Co.,Ltd.,Beishan Industrial Zone,Yantian District,Shenzhen 518083,China [4]School of Life Sciences and Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations,Lanzhou University,Lanzhou 730030,China [5]State Key Laboratory of Subtropical Silviculture,Zhejiang Agriculture and Forestry University,Hangzhou 311300,China [6]State Key Laboratory of Plant Diversity and Specialty Crops,South China Botanical Garden,Chinese Academy of Sciences,Guangzhou 510650,China [7]Guangdong Provincial Key Laboratory of Applied Botany&Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement,South China Botanical Garden,Chinese Academy of Sciences,Guangzhou 510650,China [8]College of Life Sciences and Oceanography,Shenzhen University,Shenzhen 518060,China [9]State Key Laboratory of Efficient Production of Forest Resources,Beijing Forestry University,Beijing 100083,China

出　　处：《Plant Communications》2024年第7期157-177,共21页植物通讯（英文）

基　　金：supported by the National Natural Science Foundation of China(NSFC)(no.91125027);GRF grants(CUHK codes 14148916 and 14104521);AoE grants(AoE/M-05/12 and AoE/M-403/16)from the Research Grants Council(RGC)of Hong Kong;the NSFC-RGC Joint Scheme(N_CUHK452/17);the National Key Research and Development Program,Key Innovative and Collaborative Science and Technology Scheme for Hong Kong,Macao,and Taiwan(2017YFE0191100);direct grants from the Chinese University of Hong Kong;and the China Postdoctoral Science Foundation(2023M741234).

摘　　要：Plants that grow in extreme environments represent unique sources of stress-resistance genes and mechanisms.Ammopiptanthus mongolicus(Leguminosae)is a xerophytic evergreen broadleaf shrub native to semi-arid and desert regions;however,its drought-tolerance mechanisms remain poorly understood.Here,we report the assembly of a reference-grade genome for A.mongolicus,describe its evolutionary history within the legume family,and examine its drought-tolerance mechanisms.The assembled genome is 843.07 Mb in length,with 98.7%of the sequences successfully anchored to the nine chromosomes of A.mongolicus.The genome is predicted to contain 47611 protein-coding genes,and 70.71%of the genome is composed of repetitive sequences;these are dominated by transposable elements,particularly longterminal-repeat retrotransposons.Evolutionary analyses revealed two whole-genome duplication(WGD)events at 130 and 58 million years ago(mya)that are shared by the genus Ammopiptanthus and other legumes,but no species-specific WGDs were found within this genus.Ancestral genome reconstruction revealed that the A.mongolicus genome has undergone fewer rearrangements than other genomes in the legume family,confirming its status as a"relict plant".Transcriptomic analyses demonstrated that genes involved in cuticular wax biosynthesis and transport are highly expressed,both under normal conditions and in response to polyethylene glycol-induced dehydration.Significant induction of genes related to ethylene biosynthesis and signaling was also observed in leaves under dehydration stress,suggesting that enhanced ethylene response and formation of thick waxy cuticles are two major mechanisms of drought tolerance in A.mongolicus.Ectopic expression of AmERF2,an ethylene response factor unique to A.mongolicus,can markedly increase the drought tolerance of transgenic Arabidopsis thaliana plants,demonstrating the potential for application of A.mongolicus genes in crop improvement.

关 键 词：Ammopiptanthus mongolicus genome sequencing genome evolution drought tolerance cuticular wax ETHYLENE 

分 类 号：Q94[生物学—植物学]