Zhong Yan, Wu Wei, Sun Chenyu, Zou Peishan, Liu Ying, Dai Seping, Zhou Renchao
State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, China.
Guangzhou Institute of Forestry and Landscape Architecture, Guangzhou, China.
Front Plant Sci. 2023 Jan 27;14:1126319. doi: 10.3389/fpls.2023.1126319. eCollection 2023.
, consisting of ~100 species diversified in tropical Asia and Oceania in the past 1-2 million years, represents an excellent example of rapid speciation in flowering plants. Trichomes on hypanthia, twigs and leaves vary markedly among species of this genus and are the most important diagnostic traits for species identification. These traits also play critical roles in contributing to differential adaptation of these species to their own habitats. Here we sequenced the genome of , a common, erect-growing species from southern China, with the aim to provide genomic insights into trichome evolution in this genus. We generated a high-quality, chromosome-level genome assembly of , with the genome size of 256.2 Mb and protein-coding gene number of 40,938. The gene families specific to, and significantly expanded in are enriched for GO terms related to trichome initiation and differentiation. We provide evidence that and its sister genus have undergone two whole genome duplications (WGDs) after the triplication event (γ) shared by all core eudicots. Preferential retention of trichome development-related transcription factor genes such as C2H2, bHLH, HD-ZIP, WRKY, and MYB after both WGDs might provide raw materials for trichome evolution and thus contribute to rapid species diversification in . Our study provides candidate transcription factor genes related to trichome evolution in , which can be used to evolutionary and functional studies of trichome diversification among species of this genus.
在过去的100万至200万年中，由约100个物种组成，在热带亚洲和大洋洲多样化，是开花植物快速物种形成的一个极好例子。该属物种间花托、嫩枝和叶片上的毛状体差异显著，是物种鉴定的最重要诊断特征。这些特征在促进这些物种对自身栖息地的差异适应方面也起着关键作用。在这里，我们对一种来自中国南方的常见直立生长物种的基因组进行了测序，目的是为该属毛状体的进化提供基因组见解。我们生成了该物种高质量的染色体水平基因组组装，基因组大小为256.2 Mb，蛋白质编码基因数量为40,938个。该物种特有的且在其中显著扩增的基因家族富含与毛状体起始和分化相关的基因本体术语。我们提供的证据表明，该物种及其姐妹属在所有核心真双子叶植物共享的三倍化事件（γ）之后经历了两次全基因组复制（WGD）。两次WGD后，C2H2、bHLH、HD-ZIP、WRKY和MYB等毛状体发育相关转录因子基因的优先保留可能为毛状体进化提供原材料，从而促进该物种的快速物种多样化。我们的研究提供了与该物种毛状体进化相关的候选转录因子基因，可用于该属物种间毛状体多样化的进化和功能研究。
