State Key Laboratory of Food Science and Technology, Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi, 214122, China.
State Key Laboratory of Food Science and Technology, Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi, 214122, China.
Chemosphere. 2019 Jul;227:522-532. doi: 10.1016/j.chemosphere.2019.04.076. Epub 2019 Apr 11.
With increasing application of rare earth elements (REEs), the resulting environmental safety has attracted extensive attention. When REEs act on plant leaves, REEs can initiate endocytosis in leaf cells, causing more REEs enter plant cells and then severe damage to plants. But when REEs directly act on plant roots, whether and how REEs affect the endocytosis in root cells remain unknown. Here, we characterized effects of lanthanum [La(III)], a REE with high accumulation in environment, on the endocytosis in root cells of Arabidopsis thaliana, and revealed effect mechanism from the perspective of DNA methylation. We found that La(III) enhanced the endocytosis in root cells and the extent of enhancement depended on the dose and time of La(III) exposure: 160 μM > 80 μM >30 μM (12 h); 80 μM > 30 μM >160 μM (24 h); 24 h > 12 h. La(III)-enhanced endocytosis in root cells resulted from DNA methylation, which was closely related to the expression level of genes encoding DNA methylases/demethylases: CMT3, DRM2 and DNMT2 for 12 h, MET1, CMT1, CMT2, CMT3, DRM2, DNMT2, ROS1, DME, DML2, DML5a, and DML5b for 24 h. Conversely, enhanced endocytosis also promoted the expression level of genes encoding DNA methylases/demethylases. Our findings provide references for understanding the mechanisms by which REEs impact plants.
随着稀土元素 (REEs) 的应用越来越广泛，其对环境的安全性引起了广泛关注。当 REEs 作用于植物叶片时，REEs 可以引发叶细胞内吞作用，导致更多的 REEs 进入植物细胞，从而对植物造成严重损害。但是，当 REEs 直接作用于植物根部时，REEs 是否以及如何影响根细胞内吞作用尚不清楚。在这里，我们研究了一种在环境中高度积累的 REE 镧 [La(III)] 对拟南芥根细胞内吞作用的影响，并从 DNA 甲基化的角度揭示了其作用机制。我们发现 La(III) 增强了根细胞内吞作用，增强程度取决于 La(III)暴露的剂量和时间：160μM>80μM>30μM（12h）；80μM>30μM>160μM（24h）；24h>12h。La(III)增强根细胞内吞作用是由 DNA 甲基化引起的，这与编码 DNA 甲基转移酶/去甲基化酶的基因表达水平密切相关：12h 时为 CMT3、DRM2 和 DNMT2；24h 时为 MET1、CMT1、CMT2、CMT3、DRM2、DNMT2、ROS1、DME、DML2、DML5a 和 DML5b。相反，增强的内吞作用也促进了编码 DNA 甲基转移酶/去甲基化酶的基因的表达水平。我们的研究结果为理解 REEs 影响植物的机制提供了参考。
