Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road MS978-4101, Berkeley, California 94720, United States.
J Proteome Res. 2011 Apr 1;10(4):1571-82. doi: 10.1021/pr1009433. Epub 2011 Feb 28.
The plant cell cytosol is a dynamic and complex intracellular matrix that, by definition, contains no compartmentalization. Nonetheless, it maintains a wide variety of biochemical networks and often links metabolic pathways across multiple organelles. There have been numerous detailed proteomic studies of organelles in the model plant Arabidopsis thaliana, although no such analysis has been undertaken on the cytosol. The cytosolic protein fraction from cell suspensions of Arabidopsis thaliana was isolated and analyzed using offline strong cation exchange liquid chromatography and LC-MS/MS. This generated a robust set of 1071 cytosolic proteins. Functional annotation of this set revealed major activities in protein synthesis and degradation, RNA metabolism and basic sugar metabolism. This included an array of important cytosol-related functions, specifically the ribosome, the set of tRNA catabolic enzymes, the ubiquitin-proteasome pathway, glycolysis and associated sugar metabolism pathways, phenylpropanoid biosynthesis, vitamin metabolism, nucleotide metabolism, an array of signaling and stress-responsive molecules, and NDP-sugar biosynthesis. This set of cytosolic proteins provides for the first time an extensive analysis of enzymes responsible for the myriad of reactions in the Arabidopsis cytosol and defines an experimental set of plant protein sequences that are not targeted to subcellular locations following translation and folding in the cytosol.
植物细胞质是一个动态而复杂的细胞内基质，根据定义，它不含分隔。尽管如此，它仍然维持着各种各样的生化网络，并经常将代谢途径连接到多个细胞器。尽管已经对模式植物拟南芥的细胞器进行了许多详细的蛋白质组学研究，但尚未对细胞质进行此类分析。使用离线强阳离子交换液相色谱和 LC-MS/MS 分离和分析了来自拟南芥细胞悬浮液的细胞质蛋白部分。这产生了一组稳健的 1071 种细胞质蛋白。对该组的功能注释揭示了蛋白质合成和降解、RNA 代谢和基本糖代谢的主要活性。这包括一系列重要的细胞质相关功能，特别是核糖体、一组 tRNA 分解代谢酶、泛素-蛋白酶体途径、糖酵解和相关糖代谢途径、苯丙烷生物合成、维生素代谢、核苷酸代谢、一系列信号和应激响应分子以及 NDP-糖生物合成。这组细胞质蛋白首次对拟南芥细胞质中众多反应负责的酶进行了广泛分析，并定义了一组实验性的植物蛋白质序列，这些序列在细胞质中翻译和折叠后不针对亚细胞位置。
