Laboratory of Plant and Molecular Biology, The Rockefeller University, New York, NY 10065, USA.
BMC Plant Biol. 2012 May 3;12:62. doi: 10.1186/1471-2229-12-62.
Over application of phosphate fertilizers in modern agriculture contaminates waterways and disrupts natural ecosystems. Nevertheless, this is a common practice among farmers, especially in developing countries as abundant fertilizers are believed to boost crop yields. The study of plant phosphate metabolism and its underlying genetic pathways is key to discovering methods of efficient fertilizer usage. The work presented here describes a genome-wide resource on the molecular dynamics underpinning the response and recovery in roots and shoots of Arabidopsis thaliana to phosphate-starvation.
Genome-wide profiling by micro- and tiling-arrays (accessible from GEO: GSE34004) revealed minimal overlap between root and shoot transcriptomes suggesting two independent phosphate-starvation regulons. Novel gene expression patterns were detected for over 1000 candidates and were classified as either initial, persistent, or latent responders. Comparative analysis to AtGenExpress identified cohorts of genes co-regulated across multiple stimuli. The hormone ABA displayed a dominant role in regulating many phosphate-responsive candidates. Analysis of co-regulation enabled the determination of specific versus generic members of closely related gene families with respect to phosphate-starvation. Thus, among others, we showed that PHR1-regulated members of closely related phosphate-responsive families (PHT1;1, PHT1;7-9, SPX1-3, and PHO1;H1) display greater specificity to phosphate-starvation than their more generic counterparts.
Our results uncover much larger, staged responses to phosphate-starvation than previously described. To our knowledge, this work describes the most complete genome-wide data on plant nutrient stress to-date.
现代农业中磷酸盐肥料的过度应用会污染水道并破坏自然生态系统。然而，这是农民的常见做法，尤其是在发展中国家，因为大量肥料被认为可以提高作物产量。研究植物磷酸盐代谢及其潜在的遗传途径是发现高效肥料使用方法的关键。本研究描述了一个关于拟南芥根和地上部对磷酸盐饥饿响应和恢复的分子动力学的全基因组资源。
通过微阵列和 tiling-array 的全基因组分析（可从 GEO 获得：GSE34004）揭示了根和地上部转录组之间最小的重叠，表明存在两个独立的磷酸盐饥饿调控子。超过 1000 个候选基因的新基因表达模式被检测到，并被分类为初始、持续或潜伏应答者。与 AtGenExpress 的比较分析确定了多个刺激下共同调控的基因群。激素 ABA 在调节许多磷酸盐应答候选基因方面发挥了主导作用。共调控分析能够确定密切相关基因家族的特定成员和通用成员与磷酸盐饥饿的关系。因此，除其他外，我们表明 PHR1 调节的密切相关磷酸盐应答家族（PHT1;1、PHT1;7-9、SPX1-3 和 PHO1;H1）对磷酸盐饥饿的特异性大于其更通用的对应物。
我们的结果揭示了对磷酸盐饥饿的反应比以前描述的要大得多、分阶段。据我们所知，这是迄今为止关于植物营养胁迫的最完整的全基因组数据。
