Decoration of phytochemicals contributes to the majority of metabolic diversity in nature, whereas how this process alters the biological functions of their precursor molecules remains to be investigated. Flavones, an important yet overlooked subclass of flavonoids, are most commonly conjugated with sugar moieties by UDP-dependent glycosyltransferases (UGTs). Here, we report that the natural variation of rice flavones is mainly determined by OsUGT706D1 (flavone 7-O-glucosyltransferase) and OsUGT707A2 (flavone 5-O-glucosyltransferase). UV-B exposure and transgenic evaluation demonstrate that their allelic variation contributes to UV-B tolerance in nature. Biochemical characterization of over 40 flavonoid UGTs reveals their differential evolution in angiosperms. These combined data provide biochemical insight and genetic regulation into flavone biosynthesis and additionally suggest that adoption of the positive alleles of these genes into breeding programs will likely represent a potential strategy aimed at producing stress-tolerant plants.

The objective of our study was to assess the radioprotective effect of flavonoids extracted from Rosa roxburghii Tratt (FRT) and investigate the role of Bcl-2(Ca(2+))/Caspase-3/PARP-1 pathway in radiation-induced apoptosis. Cells and mice were exposed to (60)Co γ-rays at a dose of 6 Gy. The radiation treatment induced significant effects on tissue pathological changes, apoptosis, Ca(2+), ROS, DNA damage, and expression levels of Bcl-2, Caspase-3 (C-Caspase-3), and PARP-1. The results showed that FRT acted as an antioxidant, reduced DNA damage, corrected the pathological changes of the tissue induced by radiation, promoted the formation of spleen nodules, resisted sperm aberration, and protected the thymus. FRT significantly reduced cell apoptosis compared with the irradiation group. The expression of Ca(2+) and C-Caspase-3 was decreased after FRT treatment compared with the radiation-treated group. At the same time, expression of prototype PARP-1 and Bcl-2 increased, leading to a decrease in the percentage of apoptosis cells in FRT treatment groups. We conclude that FRT acts as a radioprotector. Apoptosis signals were activated via the Bcl-2(Ca(2+))/Caspase-3/PARP-1 pathway in irradiated cells and FRT inhibited this pathway of apoptosis by down-regulation of C-Caspase-3 and Ca(2+) and up-regulation of prototype PARP-1 and Bcl-2.

Background: To study the radioprotective effects of flavonoids from Rosa roxburghii Tratt (FRT). Materials and Methods: The radioprotective effects of FRT were investigated by examining cell viability, 30-day survival of mice and the number of colony-forming units in spleen (CFU-S) after total-body 60Co irradiation. Results: The survival rates of irradiated cells gradually increased with increasing concentrations of FRT. The survival rate was the highest at 87% with a concentration of 30 µg/mL. Pretreatment with FRT was needed to realize its radioprotective activity in mice at the dose of 60 mg/kg. With the increasing doses of 30 mg/kg, 60 mg/kg and 120 mg/kg, the numbers of CFU-S increased, and were significantly different compared with the control group. Conclusions: Pretreatment with FRT prior to irradiation resulted in significantly higher cell survival at 24 h after 5 Gy radiation, increased 30-day survival in mice after exposure to a potentially lethal dose of 8 Gy, and resulted in a higher number of CFU-S in mice after exposure to a dose of 6 Gy. These results collectively indicate that FRT is an effective radioprotective agent.

NSCLC constitutes approximately 85% of lung cancers and remains a large threat to health worldwide. 1 Increasing numbers of NSCLC therapeutic strategies have been developed in recent years, however tumor metastasis is still the major effect inducing a limited prognosis and poor overall survival rate. At present, most studies have focused on changes in metastatic biochemical signals, 2,3 but less attention has been paid to intracellular mechanical activities in NSCLC motility.

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