Answering longstanding plant ecology questions with new technology: the effects of changes in leaf proteins with age

叶总氮对生态系统中的主要过程是重要的。它被用作碳固定的预测指标，因为光合作用蛋白是叶片氮的一大部分。然而，叶片的氮也可能被分配给与胁迫反应和防御相关的蛋白质，而光合作用蛋白质的损失。我们的工作假说可能解释了两个重要的生态模式：光合作用氮素利用效率随着叶龄的下降；以及不同物种和生境衰老叶片的低和可变的氮素回收水平。新的定量蛋白质组学方法与蛋白质功能分类相结合，可以回答数十种澳大利亚本土植物的这些问题。

Total leaf nitrogen is important for major processes in ecosystems. It is used as a predictor for carbon fixation because photosynthesis proteins are a large fraction of leaf nitrogen. Yet leaf nitrogen may also be allocated to stress-response and defense-related proteins at the expense of photosynthesis proteins. Our working hypothesis might explain two important ecological patterns: the decline of photosynthetic nitrogen use efficiency with leaf age; and, low and variable nitrogen recovery levels from senescent leaves across species and habitats. New quantitative proteomics methods together with protein functional categorisation can answer these questions across dozens of Australian native plant species.