Lateral roots but not root hairs contribute to high uptake of manganese and cadmium in rice
Lateral roots but not root hairs contribute to high uptake of manganese and cadmium in rice
复制标题
侧根而非根毛有助于水稻对锰和镉的高吸收
DOI：
10.1093/jxb/erab329
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发表时间：
2021
影响因子：
6.9
通讯作者：
Ma Jian Feng
中科院分区：
文献类型：
--
作者：
Yu En;Yamaji Naoki;Mao Chuanzao;Wang Hua;Ma Jian Feng
水稻（Oryza sativaL.）可通过根系（包括冠根、侧根和根毛）的吸收在茎部积累高锰（Mn）。我们利用两个侧根缺陷突变体（osiaa11）和根毛缺陷突变体（osrhl1）研究了侧根和根毛在锰和镉（Cd）吸收中的作用。对锰和镉的吸收显著低于野生型“卡萨拉斯”，但野生型与“卡萨拉斯”之间无显著差异。此外，动力学研究表明，在较宽的锰浓度范围内，锰摄取肌量远低于野生型和野生型。侧根在锰和镉吸收中的作用在侧根形成缺陷的日本稻突变体中得到进一步证实。我们发现Mn转运体天然耐药相关巨噬细胞蛋白5（OsNRAMP5）的表达比野生型低，但金属耐受蛋白9 （OsMTP9）的表达不高；然而，osrhl1与野生型之间没有差异。免疫染色显示OsNRAMP5和OsMTP9定位于冠根和侧根的外表皮和内表皮，而不定位于根毛。综上所述，我们的研究结果表明，侧根而不是根毛在水稻高锰镉吸收中起重要作用。
Rice (Oryza sativaL.) can accumulate high manganese (Mn) in the shoots through uptake by the roots, which consist of crown roots, lateral roots and root hairs. We investigated the role of lateral roots and root hairs in Mn and cadmium (Cd) uptake by using twoindicarice mutants defective in formation of lateral roots (osiaa11) and root hairs (osrhl1). The uptake of Mn and Cd inosiaa11was significantly lower than that in wild type ‘Kasalath’, but there was no difference between wild type andosrhl1. Furthermore, a kinetic study showed that Mn uptake inosiaa11was much lower than that in wild type andosrhl1across a wide range of Mn concentrations. The role of lateral roots in Mn and Cd uptake was further confirmed in ajaponicarice mutant defective in lateral root formation. We found that expression of Mn transporter geneNatural Resistance-Associated Macrophage Protein 5(OsNRAMP5),but not ofMetal Tolerance Protein 9 (OsMTP9), was lower inosiaa11than in wild type; however, there were no differences betweenosrhl1and the wild type. Immunostaining showed that OsNRAMP5 and OsMTP9 were localized in the exodermis and endodermis of crown roots and lateral roots, but not in the root hairs. Taken together, our results indicate that lateral roots, but not root hairs, play an important role in high Mn and Cd uptake in rice.