ABSTRACT
To investigate changes in transcript and relative protein levels in response to salicylic acid regulation of the thermotolerance in U. prolifera, complementary transcriptome and proteome analyses were performed with U. prolifera grown at 35 °C (UpHT) and with the addition of SA at high temperature (UpSHT). At mRNA level,12,296 differentially expressed genes (DEGs) were obtained from the comparison of UpSHT with UpHT. iTRAQ-labeling proteome analysis showed that a total of 4,449 proteins were identified and reliably quantified. At mRNA level, the up-regulated genes involved in antioxidant activity were thioredoxin,peroxiredoxin,FeSOD, glutathione peroxidase, partion catalase and MnSOD. The down-regulated genes were ascorbate peroxidase, glutathione S-transferase, catalase and MnSOD. In addition, the DEGs involved in plant signal transduction pathway (such as auxin response factors, BRI1 and JAZ) were down-regulated. At protein level, the up-regulated proteins involved in carbon fixation and the down-regulated protein mainly were polyubiquitin, ascorbate peroxidase. The expression of Ca2+-binding protein, heat shock protein and photosynthesis-related proteins, EDS1 were also significantly regulated both at mRNA and protein level. The results indicated that SA alleviated the high-temperature stimulus through partion antioxidant related proteins up-regulated, JA signal pathway enchanced, Ca2+-binding proteins, photosynthesis-related proteins significantly changed, antioxidant enzyme activities increased and photosynthesis index changed.
Subject(s)
Gene Expression Profiling , Hot Temperature , Proteome/analysis , Salicylic Acid/metabolism , Stress, Physiological , Ulva/drug effects , Ulva/radiation effects , Gene Expression Regulation, Plant , Plant Proteins/analysis , RNA, Messenger/analysis , RNA, Plant/analysis , Ulva/genetics , Ulva/physiologyABSTRACT
OBJECTIVE: To investigate the seasonal variation of total flavonoid content of Farfugium japonicum and its response to stress. METHODS: The total flavonoids of Farfugium japonicum were determined by spectrophotometry in different seasons and under various stressful factors. RESULTS: The total flavonoid content in Farfugium japonicum leaves was the highest, followed by the petiole, and rhizomes (P<0.05). The total flavonoid content in the leaves in December was higher than that in other months; that in the petiole and rhizome fluctuated in different seasons (P<0.05). As the light intensity enhanced, the total flavonoids in Farfugium japonicum leaves, petioles, rhizomes showed a downward trend. With the increase of water stress, the total flavonoid content in Farfugium japonicum leaves gradually increased, that in petiole first increased and then decreased,while that in rhizomes decreased (P<0.05). With the salt stress, the total flavonoid content in leaves, petioles and rhizomes of Farfugium japonicum showed a decreasing trend (P<0.05). With the increasing of temperature, the total flavonoid content in the leaves showed a gradually increasing trend; that in petiole first decreased and then increased,while that in the rhizomes first increased and then decreased (P<0.05). CONCLUSION: The total flavonoids of Farfugium japonicum fluctuate with the change of seasons and that in different parts of the plant has different responses to ecological stressful factors.
