Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region.
Chemosphere. 2012 Nov;89(10):1248-54. doi: 10.1016/j.chemosphere.2012.07.054. Epub 2012 Sep 1.
As a silicon hyperaccumulator, lowland rice takes up higher levels of As than many other plants due to silicic acid and arsenite sharing the same transporters (Lsi1 and Lsi2). Glomus intraradices (AH01) was inoculated to rice under different arsenite concentrations (0, 2 and 8 μM) in order to investigate the interactions between arbuscular mycorrhizal fungus and rice on the accumulation of arsenite. The relative mRNA expressions of Lsi1 and Lsi2 resulted in a down-regulating trend in mycorrhizal plants. Under 2 μM arsenite treatments, Lsi1 and Lsi2 were significantly decreased, by 0.7-fold (P<0.05) and 0.5-fold (P<0.01), respectively, in mycorrhizal plants when compared with non-mycorrhizal plants. This led to the decrease of arsenite uptake per unit of root dry mass. No organic As species were detected in both roots and shoots. The As(III)/As(V) ratios indicated that mycorrhizal plants immobilized most of the arsenite proportion in the roots and prevented its translocation from the roots to the shoots.
作为一种硅超积累植物，由于硅酸和亚砷酸盐共享相同的转运蛋白（Lsi1 和 Lsi2），水稻比许多其他植物吸收更高水平的砷。为了研究丛枝菌根真菌与水稻在亚砷酸盐积累方面的相互作用，在不同亚砷酸盐浓度（0、2 和 8 μM）下将 Glomus intraradices（AH01）接种到水稻中。结果表明，Lsi1 和 Lsi2 的相对 mRNA 表达呈下调趋势。在 2 μM 亚砷酸盐处理下，与非菌根植物相比，菌根植物中 Lsi1 和 Lsi2 的表达量分别显著下降了 0.7 倍（P<0.05）和 0.5 倍（P<0.01），导致单位根干质量对亚砷酸盐的吸收减少。在根和地上部分都没有检测到有机砷形态。As(III)/As(V) 比值表明，菌根植物将大部分亚砷酸盐固定在根部，防止其从根部向地上部分转移。
