O-Phosphorylation (phosphorylation of the hydroxyl-group of S, T, and Y residues) is among the first described and most thoroughly studied posttranslational modification (PTM). Y-Phosphorylation, catalyzed by Y-kinases, is a key step in both signal transduction and regulation of enzymatic activity in mammalian systems. Canonical Y-kinase sequences are absent from plant genomes/kinomes, often leading to the assumption that plant cells lack O-phospho-l-tyrosine (pY). However, recent improvements in sample preparation, coupled with advances in instrument sensitivity and accessibility, have led to results that unequivocally disproved this assumption. Identification of hundreds of pY-peptides/proteins, followed by validation using genomic, molecular, and biochemical approaches, implies previously unappreciated roles for this "animal PTM" in plants. Herein, we review extant results from studies of pY in plants and propose a strategy for preparation and analysis of pY-peptides that will allow a depth of coverage of the plant pY-proteome comparable to that achieved in mammalian systems.

中文翻译：

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基于质谱的植物蛋白质组学中磷酸酪氨酸的鉴定。

O磷酸化（S，T和Y残基的羟基磷酸化）是最早描述和研究最深入的翻译后修饰（PTM）之一。Y激酶催化的Y磷酸化是哺乳动物系统中信号转导和酶活性调节的关键步骤。植物基因组/激酶组中缺少典型的Y激酶序列，通常导致人们认为植物细胞缺乏O-磷酸-1-酪氨酸（pY）。但是，最近样品制备的改进，加上仪器灵敏度和可及性的提高，已导致结果明确证明了这一假设。鉴定出数百种pY肽/蛋白质，然后使用基因组，分子和生化方法进行验证，这意味着该“动物PTM”以前没有被认识到的作用 在植物中。本文中，我们回顾了植物中pY研究的现有结果，并提出了制备和分析pY肽的策略，该策略可使植物pY蛋白质组的覆盖深度与在哺乳动物系统中可比。