Department of Biological Sciences and Chemistry, University of Nizwa, Nizwa, Oman.
Department of Biology, United Arab Emirates University, P.O. Box 15551, Al-Ain, United Arab Emirates.
Plant Physiol Biochem. 2018 Jun;127:211-222. doi: 10.1016/j.plaphy.2018.03.028. Epub 2018 Mar 26.
Although abundantly present in soils, inorganic phosphate (Pi) acquisition by plants is highly dependent on the transmembrane phosphate transporter (PT) gene family. Cucumber (Cucumis sativus) requires a large amount of phosphorus (P). The purpose of this study was to isolate the CsPT2-1 from cucumber roots, and to determine the influence of Pi nutrition on cucumber growth, metabolism and transcript levels of CsPT2-1 in tissues. Full length CsPT2-1 was cloned and phylogenetically identified. In two greenhouse experiments, P-deficient seedlings provided with low or high P concentrations were sampled at 10 and 21 days post treatment, respectively. Addition of P dramatically reduced growth of roots but not shoots. Supplying plants with high P resulted in increased total protein in leaves. Acid phosphatase activity increased significantly in leaves at any rate higher than 4 mM P. Increasing P concentration had a notable decrease in glucose concentrations in leaves of plants supplied with >0.5 mM P. In roots, glucose and starch concentrations increased with increasing P supply. Steady-state transcript levels of CsPT2-1 were high in P-deprived roots, but declined when plants were provided >10 mM P. To our knowledge, this is the first report focusing on a PT and its expression levels in cucumber.
尽管土壤中无机磷（Pi）含量丰富，但植物对其的吸收高度依赖于跨膜磷转运蛋白（PT）基因家族。黄瓜（Cucumis sativus）需要大量的磷（P）。本研究的目的是从黄瓜根部分离出 CsPT2-1，并确定 Pi 营养对黄瓜生长、代谢以及组织中 CsPT2-1 转录水平的影响。克隆并系统进化鉴定全长 CsPT2-1。在两个温室实验中，分别在处理后 10 天和 21 天，用低或高 P 浓度处理 P 缺乏的幼苗。添加 P 会显著抑制根的生长，但不影响地上部分。高 P 供应会增加叶片中的总蛋白含量。在任何高于 4 mM P 的浓度下，叶片中的酸性磷酸酶活性都会显著增加。在叶片中提供高于 0.5 mM P 时，葡萄糖浓度会明显降低。在根系中，随着 P 供应的增加，葡萄糖和淀粉浓度增加。在 P 缺乏的根中，CsPT2-1 的稳态转录水平较高，但当植物提供高于 10 mM P 时，其转录水平下降。据我们所知，这是第一篇聚焦于黄瓜 PT 及其表达水平的报告。
