The MAPKs are activated by a variety of cellular stimuli to participate in a series of signaling cascades and mediate diverse intracellular responses. One potential target of the MAPKs is Op18/stathmin, a molecule that acts as an integrator of diverse cell signaling pathways and regulates the dynamics of microtubules, which are involved in modulating a variety of cellular processes, including cell cycle progression and cell growth. Our study focused on the regulation of the MAPK‐mediated Op18/stathmin signaling pathway, which is triggered by the Epstein–Barr virus‐encoded latent membrane protein 1 ( LMP1 ) oncogene in nasopharyngeal carcinoma cells. The results showed that the activity of MAPK, which was induced by LMP1, varied with cell cycle progression; LMP1 upregulated phosphorylation of ERK during the G1/S phase, but negatively regulated phosphorylation of ERK during the G2/M phase. We found that the regulation of Op18/stathmin signaling by LMP1 was mainly mediated through ERK. The inhibition of LMP1 expression attenuated the interaction of ERK with Op18/stathmin and promoted microtubule depolymerization. These findings indicate the existence of a new cell cycle‐associated signaling pathway in which LMP1 regulates ERK‐mediated Op18/stathmin signaling. (Cancer Sci 2012; 103: 993–999)
Previous study has demonstrated that the riboflavin treatment promoted the early ripening of the ‘Kyoho’ grape berry. However, the molecular mechanism causing this was unclear. In order to reveal the regulation mechanism of riboflavin treatment on grape berry development and ripening, the different berry developmental stages of the ‘Kyoho’ berry treated with 0.5 mmol/L of riboflavin was sampled for transcriptome profiling. RNA-seq revealed that 1526 and 430 genes were up-regulated and down-regulated, respectively, for the comparisons of the treatment to the control. TCseq analysis showed that the expression patterns of most of the genes were similar between the treatment and the control, except for some genes that were related to the chlorophyll metabolism, photosynthesis–antenna proteins, and photosynthesis, which were revealed by the enrichment analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The differentially expressed genes and weighted gene co-expression network analysis (WGCNA) analysis identified some significantly differentially expressed genes and some hub genes, including up-regulation of the photosynthesis-related ELIP1 and growth and development-related GDSL; and down-regulation of the oxidative stress-related ATHSP22 and berry softening-related XTH32 and GH9B15. The results suggested that the riboflavin treatment resulted in the variations of the expression levels of these genes, and then led to the early ripening of the ‘Kyoho’ berry.
Tree peony is a unique oil plant resource in China, and tree peony seed oil is one of the healthy edible oils with a very promising future. However, the main oil tree peony cultivars promoted in China are Paeonia ostii ‘Fengdan’ and Paeonia rockii. In order to explore new oil tree peony cultivars, 68 tree peony cultivars were investigated and cultivars with oil potential were selected by cluster analysis and grey relational analysis (GRA) in this study. The results demonstrated that the 68 cultivars varied significantly in terms of agronomic characteristics (p < 0.05), with the coefficient of variation in seed yield per plant reaching a high of 75.36%. The oil content of 46 cultivars was higher than ‘Fengdan’ (20.87 ± 0.26%) and ‘Zibanbai’ (21.24 ± 1.01%), while the alpha-linolenic acids and total unsaturated fatty acid contents of 26 cultivars were higher than ‘Fengdan’ (39.79 ± 1.13% and 88.99 ± 0.47%) and ‘Zibanbai’ (40.51 ± 0.09% and 93.59 ± 0.09%). Finally, three cultivars with better integrated traits were selected by cluster analysis and grey relational analysis (GRA), comprising of ‘Changshoule’, ‘Xianchizhenghui’, and ‘Yupantuojin’. The contents of alpha-linolenic acids and total unsaturated fatty acids in ‘Changshoule’ (47.98 ± 0.17% and 93.60 ± 0.08%), ‘Xianchizhenghui’ (49.44 ± 0.63% and 93.80 ± 0.06%), and ‘Yupantuojin’ (40.46 ± 0.26% and 93.58 ± 0.06%) were higher than that of ‘Fengdan’ (39.79 ± 1.13% and 88.99 ± 0.47%). In general, these cultivars can be used as hybrid parental materials for breeding new excellent oil tree peony cultivars.