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Coronatine (COR) is a structural and functional analog of methyl jasmonic acid (MeJA), which can alleviate stress on plant. We studied the effects of COR on the drought stress of rice (Oryza sativa L.). Pre-treatment with COR significantly increased the biomass, relative water and proline content, and DPPH (1,1-diphenyl-2-picrylhydrazyl)-radical scavenging activity, decreased the electrolyte leakage and MDA (Malondialdehyde) content in order to maintain the stability of cell membrane. Meanwhile, we determined how COR alleviates water stress by Nipponbare gene expression profiles and cDNA microarray analyses. Seedlings were treated with 0.1 μmol L−1 COR at the three leafed stage for 12 h, followed with 17.5% polyethylene glycol (PEG). Whole genome transcript analysis was determined by employing the Rice Gene Chip (Affymetrix), a total of 870 probe sets were identified to be up or downregulated due to COR treatment under drought stress. Meanwhile, the real-time quantitative PCR (RT-qPCR) method was used to verify some genes; it indicated that there was a good agreement between the microarray data and RT-qPCR results. Our data showed that the differentially expressed genes were involved in stress response, signal transduction, metabolism and tissue structure development. Some important genes response to stress were induced by COR, which may enhance the expression of functional genes implicated in many kinds of metabolism, and play a role in defense response of rice seedling to drought stress. This study will aid in the analysis of the expressed gene induced by COR.

Background: Nuclear factor erythroid 2-related factor 2 (NFE2L2, also known as Nrf2) is associated with cellular progression and chemotherapeutic resistance in some human cancers. We tested the relationship between Nrf2 expression and survival of patients with primary brain tumors (PBTs). Methods: In order to realize Nrf2 protein expression in gliomas, Western blot analysis was performed in normal brain tissue and U87MG, LN229, GBM8401 and U118MG glioma cell lines protein lysates. Then, U87MG, LN229, and GBM8401 mRNA were applied to performed quantitative RT-PCR for detect Nrf2 gene expression in glioma cell lines. At last, immunohistochemical analysis was used to determine the expression of Nrf2 in samples from 178 PBTs and 10 non-neoplastic brain tissues. Results: In these included in vitro studies, both Nrf2 protein and mRNA expression in all human glioma cell lines were higher than normal brain tissue. Similarly, on the viewpoint of immunohistochemistry, Nrf2 expression in gliomas were positively correlated with World Health Organization (WHO) grades. Additionally, compared with the expression of Nrf2 in non-neoplastic brain tissue, expression in meningiomas was of a stronger intensity and was present in a higher percentage of cells. Furthermore, scores were significantly higher in WHO grade II than in WHO grade I meningiomas. Finally, overall survival tended to be shorter in patients whose PBTs had higher expression of Nrf2, although the correlation was not statistically significant. Conclusions: Nrf2 overexpression positively correlated with WHO grade in gliomas and meningiomas. On the other hand, Nrf2 immunohistochemical stain could help pathologists to differentiate atypical meningiomas from benign tumors. Therefore, Nrf2 expression may be a useful biomarker to predict WHO grade and cellular behavior of PBTs. [ABSTRACT FROM AUTHOR]