Cluster of Excellence on Plant Sciences (CEPLAS), Institute for Plant Sciences, University of Cologne, D-50674 Cologne, Germany.
Department of Plant Molecular Genetics, Centro Nacional de Biotecnologia, Consejo Superior de Investigaciones Científicas (CNB-CSIC), 28049 Madrid, Spain.
Essays Biochem. 2022 Aug 5;66(2):219-228. doi: 10.1042/EBC20210058.
Several protein homeostasis (proteostasis) pathways safeguard the integrity of thousands of proteins that localize in plant chloroplasts, the indispensable organelles that perform photosynthesis, produce metabolites, and sense environmental stimuli. In this review, we discuss the latest efforts directed to define the molecular process by which proteins are imported and sorted into the chloroplast. Moreover, we describe the recently elucidated protein folding and degradation pathways that modulate the levels and activities of chloroplast proteins. We also discuss the links between the accumulation of misfolded proteins and the activation of signalling pathways that cope with folding stress within the organelle. Finally, we propose new research directions that would help to elucidate novel molecular mechanisms to maintain chloroplast proteostasis.
几种蛋白质稳态（蛋白质平衡）途径可保护定位于植物叶绿体中的数千种蛋白质的完整性，叶绿体是进行光合作用、产生代谢物和感知环境刺激的必不可少的细胞器。在这篇综述中，我们讨论了最新的努力，旨在定义蛋白质被导入和分类到叶绿体的分子过程。此外，我们还描述了最近阐明的蛋白质折叠和降解途径，这些途径调节叶绿体蛋白质的水平和活性。我们还讨论了错误折叠蛋白质的积累与激活信号通路之间的联系，这些信号通路可应对细胞器内的折叠应激。最后，我们提出了新的研究方向，这将有助于阐明维持叶绿体蛋白质平衡的新分子机制。
