Bhaskara Govinal B, Nguyen Thao T, Yang Tsu-Hao, Verslues Paul E
Institute of Plant and Microbial Biology, Academia SinicaTaipei, Taiwan.
Front Plant Sci. 2017 Apr 11;8:523. doi: 10.3389/fpls.2017.00523. eCollection 2017.
Several studies have used short term dehydration, osmotic stress or Abscisic Acid (ABA) treatments to identify the initial protein phosphorylation-dephosphorylation responses to drought and low water potential or ABA treatments. However, longer term drought acclimation leads to altered expression of many kinases and phosphatases suggesting that it may also produce unique changes in phosphoproteome composition. To get a better overview of the state of drought-related phosphoproteomics and investigate this question of short versus longer term phosphoproteome regulation, we compared three studies analyzing short term phosphoproteome changes to recent data from our laboratory analyzing phosphoproteome changes after a longer drought acclimation treatment. There was very little overlap of phosphoproteins with putative stress-induced phosphorylation or dephosphorylation among these studies. While some of this is due to technical limitations and limited coverage of the phosphoproteome achieved by each study, biological differences and the type of stress treatment used also play a role. This comparative analysis emphasized how both short and long term analysis of physiologically relevant stress treatments, as well as validation of phosphoproteomic data, will be needed to move past just scratching the surface of the stress phosphoproteome. In drought acclimation experiments, distinguishing between changes in protein abundance versus phosphorylation stoichiometry is a key challenge. We discuss initial work in using Arabidopsis seedling transient expression combined with Phos-tag gel analysis as a way to validate drought-induced phosphorylation-dephosphorylation of candidate proteins.
多项研究利用短期脱水、渗透胁迫或脱落酸（ABA）处理来确定对干旱、低水势或ABA处理的初始蛋白质磷酸化-去磷酸化反应。然而，长期干旱适应会导致许多激酶和磷酸酶的表达发生变化，这表明它也可能在磷酸化蛋白质组组成上产生独特的变化。为了更好地了解干旱相关磷酸化蛋白质组学的状态，并研究短期与长期磷酸化蛋白质组调控的问题，我们将三项分析短期磷酸化蛋白质组变化的研究与我们实验室最近关于长期干旱适应处理后磷酸化蛋白质组变化的数据进行了比较。在这些研究中，磷酸化蛋白质与假定的应激诱导磷酸化或去磷酸化之间几乎没有重叠。虽然部分原因是技术限制以及每项研究对磷酸化蛋白质组的覆盖有限，但生物学差异和所使用的应激处理类型也起到了作用。这种比较分析强调，要深入研究应激磷酸化蛋白质组，不仅需要对生理相关应激处理进行短期和长期分析，还需要对磷酸化蛋白质组数据进行验证。在干旱适应实验中，区分蛋白质丰度变化与磷酸化化学计量变化是一项关键挑战。我们讨论了利用拟南芥幼苗瞬时表达结合Phos-tag凝胶分析作为验证候选蛋白质干旱诱导磷酸化-去磷酸化的一种初步方法。
