Sakai Yuuki, Takagi Shingo
a Department of Biological Sciences, Graduate School of Science , Osaka University , Osaka , Japan.
Plant Signal Behav. 2017 Oct 3;12(10):e1370163. doi: 10.1080/15592324.2017.1370163. Epub 2017 Aug 22.
Chloroplasts are known to maintain specific intracellular distribution patterns under specific environmental conditions, enabling the optimal performance of photosynthesis. To this end, chloroplasts are anchored in the cortical cytoplasm. In leaf epidermal cells of aquatic monocot Vallisneria, we recently demonstrated that the anchored chloroplasts are rapidly de-anchored upon irradiation with high-intensity blue light and that the process is probably mediated by the blue-light receptor phototropins. Chloroplast de-anchoring is a necessary step rendering the previously anchored chloroplasts mobile to allow their migration. In this article, based on the results obtained in Vallisneria together with those in other plant species, we briefly discussed possible modes of regulation of chloroplast anchoring and de-anchoring by actin cytoskeleton. The topics include roles of photoreceptor systems, actin-filament-dependent and -independent chloroplast anchoring, and independence of chloroplast de-anchoring from actomyosin and microtubule systems.
已知叶绿体在特定环境条件下会维持特定的细胞内分布模式，从而使光合作用达到最佳性能。为此，叶绿体锚定在皮层细胞质中。在水生单子叶植物苦草的叶片表皮细胞中，我们最近证明，高强度蓝光照射后，锚定的叶绿体迅速脱离锚定，并且该过程可能由蓝光受体向光素介导。叶绿体脱离锚定是使先前锚定的叶绿体能够移动以实现迁移的必要步骤。在本文中，基于在苦草以及其他植物物种中获得的结果，我们简要讨论了肌动蛋白细胞骨架对叶绿体锚定和脱离锚定的可能调控模式。主题包括光受体系统的作用、肌动蛋白丝依赖性和非依赖性叶绿体锚定，以及叶绿体脱离锚定与肌动球蛋白和微管系统的独立性。
