期刊：Plant Biotechnology Journal 主题：NMT验证两种基因型甜高粱镉积累的差异 标题：Comparative transcriptome combined with morphophysiological analyses revealed key factors for differential cadmium accumulation in two contrasting sweet sorghum genotypes 影响因子：6.305 检测指标：Cd2+ 通讯作者：中科院植物研究所李银心，已用NMT发表3篇SCI文献
英文摘要
Cadmium (Cd) is a widespread soil contaminant threatening human health. As an ideal energy plant, sweet sorghum (Sorghum bicolor (L.) Moench) has great potential in phytoremediation of Cd-polluted soils, although the molecular mechanisms are largely unknown. In this study, key factors responsible for differential Cd accumulation between two contrasting sweet sorghum genotypes (high-Cd accumulation one H18, and low-Cd accumulation one L69) were investigated. H18 exhibited a much higher ability of Cd uptake and translocation than L69. Furthermore, Cd uptake through symplasmic pathway and Cd concentrations in xylem sap were both higher in H18 than those in L69. Root anatomy observation found the endodermal apoplasmic barriers were much stronger in L69, which may restrict the Cd loading into xylem. The molecular mechanisms underlying these morpho-physiological traits were further dissected by comparative transcriptome analysis. Many genes involved in cell wall modification and heavy metal transport were found to be Cd responsive DEGs and/or DEGs between these two genotypes. KEGG pathway analysis found phenylpropanoid biosynthesis pathway was overrepresented, indicating this pathway may play important roles in differential Cd accumulation between two genotypes. Based on these results, a schematic representation of main processes involved in differential Cd uptake and translocation in H18 and L69 is proposed, which suggests that higher Cd accumulation in H18 depends on a multilevel coordination of efficient Cd uptake and transport, including efficient root uptake and xylem loading, less root cell wall binding, and weaker endodermal apoplasmic barriers. 中文摘要（谷歌机翻译）
镉（Cd）是一种广泛的土壤污染物，威胁着人类健康。作为一种理想的能源植物，甜高粱（Sorghum bicolor（L.）Moench）在植物修复Cd污染土壤方面具有巨大潜力，尽管其分子机制尚不清楚。
在这项研究中，研究了两个对比甜高粱基因型（高Cd积累一个H18和低Cd积累一个L69）之间差异Cd积累的关键因素。 H18表现出比L69高得多的Cd摄取和易位能力。此外，H18中通过相互作用途径的Cd摄取和木质部汁液中的Cd浓度均高于L69。根解剖观察发现L69内胚层质外屏障强度较大，可能将Cd负荷限制在木质部。
通过比较转录组分析进一步解剖这些形态生理学性状的分子机制。发现参与细胞壁修饰和重金属转运的许多基因是这两种基因型之间的Cd响应性DEG和/或DEG。 KEGG途径分析发现苯丙烷类生物合成途径过多，表明该途径可能在两种基因型之间的差异性Cd积累中起重要作用。
基于这些结果，提出了H18和L69中差异性Cd吸收和转运的主要过程的示意图，这表明H18中较高的Cd积累依赖于有效Cd吸收和转运的多级协调，包括有效的根吸收和木质部负荷，较少的根细胞壁结合，和较弱的内胚层质外障碍。
文章链接： https://doi.org/10.1111/pbi.12795 http://dx.doi.org/10.1016/j.ecoenv.2017.07.002