Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, College of Horticulture Science, Zhejiang A&F University, Hangzhou 310007, China.
Institute of Biological Chemistry, Washington State University, Pullman, WA 99164, USA.
Int J Mol Sci. 2022 Nov 4;23(21):13511. doi: 10.3390/ijms232113511.
Subcellular mRNA localization is an evolutionarily conserved mechanism to spatially and temporally drive local translation and, in turn, protein targeting. Hence, this mechanism achieves precise control of gene expression and establishes functional and structural networks during cell growth and development as well as during stimuli response. Since its discovery in ascidian eggs, mRNA localization has been extensively studied in animal and yeast cells. Although our knowledge of subcellular mRNA localization in plant cells lags considerably behind other biological systems, mRNA localization to the endoplasmic reticulum (ER) has also been well established since its discovery in cereal endosperm cells in the early 1990s. Storage protein mRNA targeting to distinct subdomains of the ER determines efficient accumulation of the corresponding proteins in different endosomal storage sites and, in turn, underlies storage organelle biogenesis in cereal grains. The targeting process requires the presence of RNA localization elements, also called zipcodes, and specific RNA-binding proteins that recognize and bind these zipcodes and recruit other factors to mediate active transport. Here, we review the current knowledge of the mechanisms and functions of mRNA localization to the ER in plant cells and address directions for future research.
亚细胞 mRNA 定位是一种进化上保守的机制，可在空间和时间上驱动局部翻译，进而实现蛋白质靶向。因此，这种机制实现了对基因表达的精确控制，并在细胞生长和发育以及刺激反应过程中建立了功能和结构网络。自在海鞘卵中发现 mRNA 定位以来，人们已经在动物和酵母细胞中对其进行了广泛研究。尽管我们对植物细胞中亚细胞 mRNA 定位的了解远远落后于其他生物系统，但自 20 世纪 90 年代初在谷类胚乳细胞中发现 mRNA 定位于内质网 (ER) 以来，这种定位也得到了很好的证实。贮藏蛋白 mRNA 靶向 ER 的不同亚域决定了相应蛋白质在不同内体贮藏部位的有效积累，进而为谷类贮藏细胞器的生物发生奠定了基础。该靶向过程需要存在 RNA 定位元件（也称为 zipcode）和特定的 RNA 结合蛋白，这些蛋白可以识别和结合这些 zipcode 并招募其他因子来介导主动运输。在这里，我们综述了植物细胞中 mRNA 定位于 ER 的机制和功能的最新知识，并探讨了未来研究的方向。
