单 位：
University Key Laboratory of Plant Biotechnology in Shandong Province, College of Life Sciences, Qingdao Agricultural University, Qingdao, Shandong 266109, Chin;University Key Laboratory of Plant Biotechnology in Shandong Province, College of Life Sciences, Qingdao Agricultural University, Qingdao, Shandong 266109, China;Shandong Academy of Forestry, Jinan, Shandong 250014, China
摘 要：
Tree peony (Paeonia suffruticosa Andrews) is a well-known ornamental plant with high economic value, but the short florescence is a key obstacle to its ornamental value and industry development. High temperature accelerates flower senescence and abscission, but the associated mechanisms are poorly understood. In this study, the tandem mass tag (TMT) proteome and label-free quantitative ubiquitome from tree peony cut flowers treated with 20 °C for 0 h (RT0), 20 °C or 28 °C for 60 h (RT60 or HT60) were examined based on morphological observation, respectively. Totally, 6 970 proteins and 1 545 lysine ubiquitinated (Kub) sites in 844 proteins were identified. Hydrophilic residues (such as glutamate and aspartate) neighboring the Kub sites were in preference, and 36.01% of the Kub sites were located on the protein surface. The differentially expressed proteins (DEPs) and Kub-DEPs in HT60 vs RT60 were mainly enriched in ribosomal protein, protein biosynthesis, secondary metabolites biosynthesis, flavonoid metabolism, carbohydrate catabolism, and auxin biosynthesis and signaling revealed by GO and KEGG analysis, accompanying the increase of endogenous abscisic acid (ABA) accumulation and decrease of endogenous indoleacetic acid (IAA) level. Additionally, the expression patterns of six enzymes (SAMS, ACO, YUC, CHS, ANS and PFK) putatively with Kub modifications were analyzed by proteome and real-time quantitative RT-PCR. The cell-free degradation assays showed PsSAMS and PsACO proteins could be degraded via the 26S proteasome system in tree peony flowers. Finally, a working model was proposed for the acceleration of flower senescence and abscission by high temperature. In summary, all results contributed to understanding the mechanism of flower senescence induced by high temperature and prolonging florescence in tree peony.
