College of Horticulture and Forestry, Huazhong Agricultural University, Wuhan, China.
Plant Cell Environ. 2021 Jun;44(6):1830-1845. doi: 10.1111/pce.14040. Epub 2021 Mar 26.
For perennials in boreal and temperate ecosystems, bud dormancy is crucial for survival in harsh winter. Dormancy is released by prolonged exposure to low temperatures and is followed by reactive growth in the spring. Lysine acetylation (Kac) is one of the major post-translational modifications (PTMs) that are involved in plant response to environmental signals. However, little information is available on the effects of Kac modification on bud dormancy release. Here, we report the dynamics of lysine acetylome in hybrid poplar (Populus tremula × Populus alba) dormant buds. A total of 7,594 acetyl-sites from 3,281 acetyl-proteins were identified, representing a large dataset of lysine acetylome in plants. Of them, 229 proteins were differentially acetylated during bud dormancy release and were mainly involved in the primary metabolic pathways. Site-directed mutagenesis enzymatic assays showed that Kac strongly modified the activities of two key enzymes of primary metabolism, pyruvate dehydrogenase (PDH) and isocitrate dehydrogenase (IDH). We thus propose that Kac of enzymes could be an important strategy for reconfiguration of metabolic processes during bud dormancy release. In all, our results reveal the importance of Kac in bud dormancy release and provide a new perspective to understand the molecular mechanisms of seasonal growth of trees.
对于北方和温带生态系统中的多年生植物来说，芽休眠对于在恶劣的冬季中生存至关重要。休眠通过长时间暴露在低温下而解除，并在春季随之发生反应性生长。赖氨酸乙酰化（Kac）是涉及植物对环境信号响应的主要翻译后修饰（PTM）之一。然而，关于 Kac 修饰对芽休眠解除的影响的信息很少。在这里，我们报告了杂种杨（Populus tremula×Populus alba）休眠芽中赖氨酸乙酰组的动态。总共鉴定了 7594 个来自 3281 个乙酰蛋白的乙酰化位点，代表了植物中赖氨酸乙酰组的大型数据集。其中，229 种蛋白质在芽休眠解除过程中发生了差异乙酰化，主要涉及初级代谢途径。定点突变酶促分析表明，Kac 强烈修饰了两种关键的初级代谢酶，丙酮酸脱氢酶（PDH）和异柠檬酸脱氢酶（IDH）的活性。因此，我们提出酶的 Kac 可能是芽休眠解除过程中代谢过程重新配置的重要策略。总之，我们的结果揭示了 Kac 在芽休眠解除中的重要性，并为理解树木季节性生长的分子机制提供了新的视角。
