Brassinosteroid-regulated Phosphoproteome in Arabidopsis thaliana

• Main Authors: Shiao-Yun Ko, 柯曉雲
• Other Authors: 阮雪芬
• Format: Others
• Language: en_US
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/85145570122427079562

碩士 === 國立臺灣大學 === 分子與細胞生物學研究所 === 100 === Brassinosteroid (BR) is a plant hormone involved in almost every stage of plant development. BR response starts from receptor kinase activation, and relays BR signal from cell surface to the nucleus by phosphorylation-mediated signaling. To date, the signaling pathway of BR has been well established at the gene expression level. However, only little information of phosphoproteins in BR signaling can be available. To investigate the global phosphorylation-regulatory responses in BR signaling, a time-dependent phosphoproteomic study was performed in Arabidopsis cells. Dimethyl labeling and TiO2 enrichment combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to characterize the phosphoproteome of BR signaling process. Our results identified 519 phosphorylated proteins from 1481 phosphorylated peptides. We further focused on significant change in quantification phosphoprotein. Changed in 12 of 402 quantitated phosphopeptides were significant. These proteins containing ribosome associated proteins, kinases and phosphatases are known to be involved in transcription, translation regulation and metabolic processes. Several proteins that may be regulated by BR were not known previously. This study uncovered a wide-range of phosphorylated proteins in response to BR signaling. Our results not only provide useful information for the phosphoproteomic research in plant hormone, but also reveal a new picture of signal transduction on BR regulation.