Max-Planck Institute for Molecular Plant Physiology, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany.
Trends Plant Sci. 2011 Sep;16(9):489-98. doi: 10.1016/j.tplants.2011.05.008.
In cellular circumstances under which carbohydrates are scarce, plants can metabolize proteins and lipids as alternative respiratory substrates. Respiration of protein is less efficient than that of carbohydrate as assessed by the respiratory quotient; however, under certain adverse conditions, it represents an important alternative energy source for the cell. Significant effort has been invested in understanding the regulation of protein degradation in plants. This has included an investigation of how proteins are targeted to the proteosome, and the processes of senescence and autophagy. Here we review these events with particular reference to amino acid catabolism and its role in supporting the tricarboxylic acid cycle and direct electron supply to the ubiquinone pool of the mitochondrial electron transport chain in plants.
在碳水化合物匮乏的细胞环境中，植物可以将蛋白质和脂质代谢为替代呼吸底物。与呼吸商评估的碳水化合物相比，蛋白质的呼吸效率较低；然而，在某些不利条件下，它是细胞的重要替代能源。人们投入了大量精力来研究植物中蛋白质降解的调节。这包括研究蛋白质如何靶向蛋白酶体，以及衰老和自噬的过程。在这里，我们特别参考氨基酸分解代谢及其在支持三羧酸循环和直接向植物线粒体电子传递链的泛醌池提供电子方面的作用，来回顾这些事件。
