文献类型： 外文期刊

作者： Wu, Xiaopei ¹ ; Zhang, Lu ³ ; Wang, Xiuyun ⁴ ; Zhang, Rengang ⁵ ; Jin, Guihua ¹ ; Hu, Yanting ¹ ; Yang, Hong ¹ ; Wu, Zhenzhen ¹ ; Ma, Yongpeng ⁵ ; Zhang, Chengjun ¹ ; Wang, Jihua ³ ;

作者机构： 1.Chinese Acad Sci, Kunming Inst Bot, Germplasm Bank Wild Species, Kunming, Peoples R China

2.Univ Chinese Acad Sci, Beijing, Peoples R China

3.Yunnan Acad Agr Sci, Natl Engn Res Ctr Ornamental Hort, Flower Res Inst, Kunming, Peoples R China

4.Zhejiang Univ, Coll Agr & Biotechnol, Genom & Genet Engn Lab Ornamental Plants, Hangzhou, Peoples R China

5.Chinese Acad Sci, Kunming Inst Bot, Yunnan Key Lab Integrat Conservat Plant Species Ex, Kunming, Peoples R China

6.Key Lab Plant Divers & Biogeog East Asia, Kunming, Peoples R China

7.Hubei Univ, Sch Life Sci, State Key Lab Biocatalysis & Enzyme Engn, Wuhan, Peoples R China

8.Zhejiang Inst Adv Technol, Haiyan Engn & Technol Ctr, Jiaxing, Peoples R China

关键词： Rhododendron delavayi; Rhododendron irroratum; genome evolution; gene duplication; anthocyanin biosynthesis; NBS-encoding genes

期刊名称：FRONTIERS IN PLANT SCIENCE （ 影响因子：5.6； 五年影响因子：6.8 ）

ISSN： 1664-462X

年卷期： 2023 年 14 卷

页码：

收录情况： SCI

摘要： BackgroundThe genus Rhododendron (Ericaceae), a species-rich and widely distributed genus of woody plants, is distinguished for the beautiful and diverse flowers. Rhododendron delavayi Franch. and Rhododendron irroratum Franch., are highly attractive species widely distributed in south-west China and abundant new varieties have been selected from their genetic resources. MethodsWe constructed chromosome-scale genome assemblies for Rhododendron delavayi and Rhododendron irroratum. Phylogenetic and whole-genome duplication analyses were performed to elucidate the evolutionary history of Rhododendron. Further, different types of gene duplications were identified and their contributions to gene family expansion were investigated. Finally, comprehensive characterization and evolutionary analysis of R2R3-MYB and NBS-encoding genes were conducted to explore their evolutionary patterns. ResultsThe phylogenetic analysis classified Rhododendron species into two sister clades, 'rhododendrons' and 'azaleas'. Whole-genome duplication (WGD) analysis unveiled only one WGD event that occurred in Rhododendron after the ancestral gamma triplication. Gene duplication and gene family expansion analyses suggested that the younger tandem and proximal duplications contributed greatly to the expansion of gene families involved in secondary metabolite biosynthesis and stress response. The candidate R2R3-MYB genes likely regulating anthocyanin biosynthesis and stress tolerance in Rhododendron will facilitate the breeding for ornamental use. NBS-encoding genes had undergone significant expansion and experienced species-specific gain and loss events in Rhododendron plants. ConclusionsThe reference genomes presented here will provide important genetic resources for molecular breeding and genetic improvement of plants in this economically important Rhododendron genus.