State Key Laboratory of Rice Biology and Breeding, China National Rice Research Institute, Hangzhou, Zhejiang, China.
Plant Molecular and Cellular Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA.
Nat Commun. 2024 Jul 11;15(1):5823. doi: 10.1038/s41467-024-50106-5.
Zinc (Zn) is an essential micronutrient but can be cytotoxic when present in excess. Plants have evolved mechanisms to tolerate Zn toxicity. To identify genetic loci responsible for natural variation of plant tolerance to Zn toxicity, we conduct genome-wide association studies for root growth responses to high Zn and identify 21 significant associated loci. Among these loci, we identify Trichome Birefringence (TBR) allelic variation determining root growth variation in high Zn conditions. Natural alleles of TBR determine TBR transcript and protein levels which affect pectin methylesterification in root cell walls. Together with previously published data showing that pectin methylesterification increase goes along with decreased Zn binding to cell walls in TBR mutants, our findings lead to a model in which TBR allelic variation enables Zn tolerance through modulating root cell wall pectin methylesterification. The role of TBR in Zn tolerance is conserved across dicot and monocot plant species.
锌（Zn）是一种必需的微量元素，但过量存在时会具有细胞毒性。植物已经进化出耐受锌毒性的机制。为了鉴定负责植物耐受锌毒性自然变异的遗传基因座，我们对根生长对高锌的反应进行了全基因组关联研究，并鉴定出 21 个显著相关的基因座。在这些基因座中，我们鉴定出 Trichome Birefringence（TBR）等位基因变异决定了在高锌条件下根生长的变异。TBR 的天然等位基因决定了 TBR 转录本和蛋白水平，从而影响根细胞壁中的果胶甲酯化。结合先前发表的数据表明，TBR 突变体中果胶甲酯化的增加伴随着细胞壁与 Zn 结合的减少，我们的研究结果提出了一个模型，即 TBR 等位基因变异通过调节根细胞壁的果胶甲酯化来实现 Zn 耐受。TBR 在 Zn 耐受中的作用在双子叶植物和单子叶植物物种中是保守的。
Zotero 插件
