Proteome-Wide Analyses Reveal the Diverse Functions of Lysine 2-Hydroxyisobutyrylation inOryza sativa
Proteome-Wide Analyses Reveal the Diverse Functions of Lysine 2-Hydroxyisobutyrylation inOryza sativa
复制标题
全蛋白质组分析揭示了稻赖氨酸 2-羟基异丁酰化的多种功能
DOI：
10.1186/s12284-020-00389-1
复制
发表时间：
2020-06-05
期刊：
影响因子：
5.5
通讯作者：
Gong, Zhiyun
中科院分区：
文献类型：
--
作者：
Xue, Chao;Qiao, Zhongying;Gong, Zhiyun
背景
赖氨酸2 - 羟基异丁酰化（Khib）是一种新发现的翻译后修饰，已知其在动物中可调节转录活性。然而，在植物和动物中对赖氨酸2 - 羟基异丁酰化修饰组的广泛研究尚未开展。
结果
在本研究中，我们利用液相色谱 - 串联质谱（LC - MS/MS）定性蛋白质组学策略，在水稻（Oryza sativa）幼苗的1596种修饰蛋白质上鉴定出4163个Khib位点。基序分析揭示了Khib位点侧翼的10个保守基序，亚细胞定位分析表明44%的Khib蛋白质定位于叶绿体。基因本体功能、京都基因与基因组百科全书（KEGG）通路以及蛋白质结构域富集分析显示，Khib发生在参与多种生物过程的蛋白质上，尤其在碳代谢和光合作用中富集。在修饰的蛋白质中，在组蛋白H2A和H2B中鉴定出20个Khib位点，而在组蛋白H4中仅鉴定出1个位点。蛋白质 - 蛋白质相互作用（PPI）网络分析进一步表明，Khib参与多种生物过程，包括核糖体活性、次生代谢物的生物合成以及代谢途径。此外，对水稻蛋白质组中赖氨酸2 - 羟基异丁酰化、乙酰化和巴豆酰化的比较表明，仅有26个常见赖氨酸位点的45种蛋白质通常被这三种翻译后修饰（PTM）所修饰。这些PTM之间修饰位点和PPI的相互作用可能形成一个具有相似和不同调控机制的复杂网络。
结论
总之，我们的研究全面描绘了水稻中的赖氨酸2 - 羟基异丁酰化修饰组，并更好地理解了其在植物中的生物学功能。
Background Lysine 2-hydroxyisobutyrylation (Khib), a newly identified post-translational modification, is known to regulate transcriptional activity in animals. However, extensive studies of the lysine 2-hydroxyisobutyrylome in plants and animals have yet to be performed. Results In this study, using LC-MS/MS qualitative proteomics strategies, we identified 4163 Khib sites on 1596 modified proteins in rice (Oryza sativa) seedlings. Motif analysis revealed 10 conserved motifs flanking the Khib sites, and subcellular localization analysis revealed that 44% of the Khib proteins are localized in the chloroplast. Gene ontology function, KEGG pathway, and protein domain enrichment analyses revealed that Khib occurs on proteins involved in diverse biological processes and is especially enriched in carbon metabolism and photosynthesis. Among the modified proteins, 20 Khib sites were identified in histone H2A and H2B, while only one site was identified in histone H4. Protein-protein interaction (PPI) network analysis further demonstrated that Khib participates in diverse biological processes including ribosomal activity, biosynthesis of secondary metabolites, and metabolic pathways. In addition, a comparison of lysine 2-hydroxyisobutyrylation, acetylation, and crotonylation in the rice proteome showed that 45 proteins with only 26 common lysine sites are commonly modified by three PTMs. The crosstalk of modified sites and PPI among these PTMs may form a complex network with both similar and different regulatory mechanisms. Conclusions In summary, our study comprehensively profiles the lysine 2-hydroxyisobutyrylome in rice and provides a better understanding of its biological functions in plants.