Lehtimäki Nina, Koskela Minna M, Mulo Paula
Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014 Turku, Finland.
Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014 Turku, Finland
Plant Physiol. 2015 Jul;168(3):768-75. doi: 10.1104/pp.15.00117. Epub 2015 Apr 24.
Posttranslational modifications of proteins are key effectors of enzyme activity, protein interactions, targeting, and turnover rate, but despite their importance, they are still poorly understood in plants. Although numerous reports have revealed the regulatory role of protein phosphorylation in photosynthesis, various other protein modifications have been identified in chloroplasts only recently. It is known that posttranslational N(α)-acetylation occurs in both nuclear- and plastid-encoded chloroplast proteins, but the physiological significance of this acetylation is not yet understood. Lysine acetylation affects the localization and activity of key metabolic enzymes, and it may work antagonistically or cooperatively with lysine methylation, which also occurs in chloroplasts. In addition, tyrosine nitration may help regulate the repair cycle of photosystem II, while N-glycosylation determines enzyme activity of chloroplastic carbonic anhydrase. This review summarizes the progress in the research field of posttranslational modifications of chloroplast proteins and points out the importance of these modifications in the regulation of chloroplast metabolism.
蛋白质的翻译后修饰是酶活性、蛋白质相互作用、靶向作用和周转率的关键效应因子，尽管其很重要，但在植物中仍未得到充分了解。尽管众多报告揭示了蛋白质磷酸化在光合作用中的调节作用，但叶绿体中的各种其他蛋白质修饰直到最近才被发现。已知翻译后N(α)-乙酰化发生在核编码和质体编码的叶绿体蛋白质中，但这种乙酰化的生理意义尚不清楚。赖氨酸乙酰化会影响关键代谢酶的定位和活性，并且它可能与同样发生在叶绿体中的赖氨酸甲基化产生拮抗或协同作用。此外，酪氨酸硝化可能有助于调节光系统II的修复循环，而N-糖基化决定了叶绿体碳酸酐酶的酶活性。本综述总结了叶绿体蛋白质翻译后修饰研究领域的进展，并指出了这些修饰在叶绿体代谢调节中的重要性。
