Quantitative Proteomic Analyses Identify STO/BBX24 -Related Proteins Induced by UV-B

Abstract

Plants use solar radiation for photosynthesis and are inevitably exposed to UV-B. To adapt to UV-B radiation, plants have evolved a sophisticated strategy, but the mechanism is not well understood. We have previously reported that STO (salt tolerance)/BBX24 is a negative regulator of UV-B-induced photomorphogenesis. However, there is limited knowledge of the regulatory network of STO in UV-B signaling. Here, we report the identification of proteins differentially expressed in the wild type (WT) and sto mutant after UV-B radiation by iTRAQ (isobaric tags for relative and absolute quantitation)-based proteomic analysis to explore differential proteins that depend on STO and UV-B signaling. A total of 8212 proteins were successfully identified, 221 of them were STO-dependent proteins in UV-B irradiated plants. The abundances of STO-dependent PSB and LHC (light-harvesting complex) proteins in sto mutants decreased under UV-B radiation, suggesting that STO is necessary to maintain the normal accumulation of photosynthetic system complex under UV-B radiation to facilitate photosynthesis photon capture. The abundance of phenylalanine lyase-1 (PAL1), chalcone synthetase (CHS), and flavonoid synthetase (FLS) increased significantly after UV-B irradiation, suggesting that the accumulation of flavonoids do not require STO, but UV-B is needed. Under UV-B radiation, STO stabilizes the structure of antenna protein complex by maintaining the accumulation of PSBs and LHCs, thereby enhancing the non-photochemical quenching (NPQ) ability, releasing extra energy, protecting photosynthesis, and ultimately promoting the elongation of hypocotyl. The accumulation of flavonoid synthesis key proteins is independent of STO under UV-B radiation. Overall, our results provide a comprehensive regulatory network of STO in UV-B signaling.

Morphophysiological and Proteomic Responses on Plants of Irradiation with Electromagnetic Waves

“…Gene expression level of glyoxalase upregulated in rice under UV irradiation, which was consistent with the change of protein levels [124]. In plant secondary metabolism, many proteins as well as their gene expression levels altered in accordance with the increasing trend of secondary metabolites, which included phenylalanine ammonia lyase, chalcone synthetase, flavonoid synthetase, and terpenoid biosynthesis-related proteins [120,122,128]. In addition, activity of phenylalanine ammonia lyase was found to be increased in Lonicera japonica under UV irradiation, which was responsible for activation of the phenylpropanoid pathway [119].…”

“…Under UV-C irradiation, protein profiles in leaves of Cynara cardunculus have been examined using 2-D PAGE and 2-D difference in-gel electrophoresis [120,121]. In the meantime, proteomic responses in plants under UV-B irradiation were the mostly studied, including the studies in Arabidopsis thaliana leaves using isobaric tags for relative and absolute quantitation (iTRAQ)-based analysis [122], Catharanthus roseus leaves using gel-free/label-free analysis [105,123], rice leaves using 2-D PAGE [124], Populus cathayana leaves using iTRAQ-based analysis [125], soybean seedlings [126]/sprouts using 2-D PAGE/iTRAQ-based analysis [127], Euphorbia kansui laticifers using iTRAQ-based analysis [128], and barley leaves using combinatory analysis of 2-D PAGE plus gel-free/label-free-based LC-MS/MS detection [106]. According to these proteomic analyses, the abundance of proteins related to photosynthesis, energy production/consumption, antioxidant reactions, and secondary metabolism under UV irradiations significantly altered (Figure 2).…”

BBX24 Interacts with DELLA to Regulate UV-B-Induced Photomorphogenesis in Arabidopsis thaliana

“…The loss-of-function mutant della caused excessive plant growth in daylight [13][14][15]. Both DELLA and UV-B can activate the phenylpropane pathway and promote the accumulation of phenolic compounds, such as flavonoids, anthocyanins, and mustard oils, to adapt to environmental changes [2,8,[34][35][36][37]. HY5 is the core transcription factor for photomorphogenesis, which regulates nearly one-third of the gene expression in the Arabidopsis genome and is also necessary for the UV-B transduction pathway [38].…”

PAXIP1-AS1 is associated with immune infiltration and predicts poor prognosis in ovarian cancer

“…All cells are stored in a humidified incubator with 5% CO 2 at 37˚C. The PAXI-P1-AS1 levels in SKOV3, A2780, and IOSE29 cell lines were identified by qRT-PCR [28][29][30]. The primer sequences used are shown in Table 1.…”