文献类型： 外文期刊

作者： Hua, Ying-peng ¹ ; Chen, Jun-fan ¹ ; Zhou, Ting ¹ ; Zhang, Tian-yu ¹ ; Shen, Dan-dan ¹ ; Feng, Ying-na ¹ ; Guan, Pan-feng ¹ ; Huang, Shao-min ² ; Zhou, Zheng-fu ³ ; Huang, Jin-yong ¹ ; Yue, Cai-peng ¹ ;

作者机构： 1.Zhengzhou Univ, Sch Agr Sci, Zhengzhou 450001, Peoples R China

2.Henan Acad Agr Sci, Inst Plant Nutrient & Environm Resources, Zhengzhou 450002, Peoples R China

3.Henan Acad Agr Sci, Wheat Res Inst, Zhengzhou 450002, Peoples R China

4.Zhengzhou Univ, Sch Life Sci, Zhengzhou 450001, Peoples R China

关键词： Allohexaploid wheat; cadmium; Cd accumulation; Cd resistance; genotypic differences; long-distance translocation; metal toxicity; multiomics; Triticum aestivum

期刊名称：JOURNAL OF EXPERIMENTAL BOTANY （ 影响因子：7.298； 五年影响因子：8.291 ）

ISSN： 0022-0957

年卷期： 2022 年 73 卷 22 期

页码：

收录情况： SCI

摘要： Cadmium (Cd) is a highly toxic heavy metal that readily enters cereals, such as wheat, via the roots and is translocated to the shoots and grains, thereby posing high risks to human health. However, the vast and complex genome of allohexaploid wheat makes it challenging to understand Cd resistance and accumulation. In this study, a Cd-resistant cultivar of wheat, 'ZM1860', and a Cd-sensitive cultivar, 'ZM32', selected from a panel of 442 accessions, exhibited significantly different plant resistance and grain accumulation. We performed an integrated comparative analysis of the morpho-physiological traits, ionomic and phytohormone profiles, genomic variations, transcriptomic landscapes, and gene functionality in order to identify the mechanisms underlying these differences. Under Cd toxicity, 'ZM1860' outperformed 'ZM32', which showed more severe leaf chlorosis, poorer root architecture, higher accumulation of reactive oxygen species, and disordered phytohormone homeostasis. Ionomics showed that 'ZM32' had a higher root-to-shoot translocation coefficient of Cd and accumulated more Cd in the grains than 'ZM1860'. Whole-genome re-sequencing (WGS) and transcriptome sequencing identified numerous DNA variants and differentially expressed genes involved in abiotic stress responses and ion transport between the two genotypes. Combined ionomics, transcriptomics, and functional gene analysis identified the plasma membrane-localized heavy metal ATPase TaHMA2b-7A as a crucial Cd exporter regulating long-distance Cd translocation in wheat. WGS- and PCR-based analysis of sequence polymorphisms revealed a 25-bp InDel site in the promoter region of TaHMA2b-7A, and this was probably responsible for the differential expression. Our multiomics approach thus enabled the identification of a core transporter involved in long-distance Cd translocation in wheat, and it may provide an elite genetic resource for improving plant Cd resistance and reducing grain Cd accumulation in wheat and other cereal crops. Multiomics analysis identifies TaHMA2b-7A as a key Cd exporter regulating long-distance translocation and improving Cd resistance and reducing grain Cd accumulation in wheat.