Kleffmann Torsten, von Zychlinski Anne, Russenberger Doris, Hirsch-Hoffmann Matthias, Gehrig Peter, Gruissem Wilhelm, Baginsky Sacha
Institute of Plant Sciences, Eidgenössische Technische Hochschule Zurich, 8092 Zurich, Switzerland.
Plant Physiol. 2007 Feb;143(2):912-23. doi: 10.1104/pp.106.090738. Epub 2006 Dec 22.
We have analyzed proteome dynamics during light-induced development of rice (Oryza sativa) chloroplasts from etioplasts using quantitative two-dimensional gel electrophoresis and tandem mass spectrometry protein identification. In the dark, the etioplast allocates the main proportion of total protein mass to carbohydrate and amino acid metabolism and a surprisingly high number of proteins to the regulation and expression of plastid genes. Chaperones, proteins for photosynthetic energy metabolism, and enzymes of the tetrapyrrole pathway were identified among the most abundant etioplast proteins. The detection of 13 N-terminal acetylated peptides allowed us to map the exact localization of the transit peptide cleavage site, demonstrating good agreement with the prediction for most proteins. Based on the quantitative etioplast proteome map, we examined early light-induced changes during chloroplast development. The transition from heterotrophic metabolism to photosynthesis-supported autotrophic metabolism was already detectable 2 h after illumination and affected most essential metabolic modules. Enzymes in carbohydrate metabolism, photosynthesis, and gene expression were up-regulated, whereas enzymes in amino acid and fatty acid metabolism were significantly decreased in relative abundance. Enzymes involved in nucleotide metabolism, tetrapyrrole biosynthesis, and redox regulation remained unchanged. Phosphoprotein-specific staining at different time points during chloroplast development revealed light-induced phosphorylation of a nuclear-encoded plastid RNA-binding protein, consistent with changes in plastid RNA metabolism. Quantitative information about all identified proteins and their regulation by light is available in plprot, the plastid proteome database (http://www.plprot.ethz.ch).
我们利用定量二维凝胶电泳和串联质谱蛋白质鉴定技术，分析了水稻（Oryza sativa）叶绿体从黄化质体光诱导发育过程中的蛋白质组动态变化。在黑暗中，黄化质体将总蛋白质量的主要部分分配给碳水化合物和氨基酸代谢，并且分配给质体基因调控和表达的蛋白质数量惊人。伴侣蛋白、光合能量代谢相关蛋白以及四吡咯途径的酶在最丰富的黄化质体蛋白中被鉴定出来。13个N端乙酰化肽段的检测使我们能够确定转运肽切割位点的精确位置，结果表明与大多数蛋白质的预测结果吻合良好。基于定量的黄化质体蛋白质组图谱，我们研究了叶绿体发育过程中早期光诱导的变化。从异养代谢向光合支持的自养代谢的转变在光照2小时后就已可检测到，并且影响了大多数基本代谢模块。碳水化合物代谢、光合作用和基因表达中的酶上调，而氨基酸和脂肪酸代谢中的酶相对丰度显著降低。参与核苷酸代谢、四吡咯生物合成和氧化还原调节的酶保持不变。叶绿体发育不同时间点的磷蛋白特异性染色显示，一种核编码的质体RNA结合蛋白发生了光诱导磷酸化，这与质体RNA代谢的变化一致。有关所有已鉴定蛋白质及其光调控的定量信息可在质体蛋白质组数据库plprot（http://www.plprot.ethz.ch）中获取。
