Conventional RNA interference (RNAi) pathways suppress eukaryotic gene expression at the transcriptional or post-transcriptional level. At the core of RNAi are small RNAs (sRNAs) and effector Argonaute (AGO) proteins. Arabidopsis AGO1 is known to bind microRNAs (miRNAs) and post-transcriptionally repress target genes in the cytoplasm. Here, we report that AGO1 also binds to the chromatin of active genes and promotes their transcription. We show that sRNAs and SWI/SNF complexes associate with nuclear AGO1 and are required for AGO1 binding to chromatin. Moreover, we show that various stimuli, including plant hormones and stresses, specifically trigger AGO1 binding to stimulus-responsive genes. Finally, we show that AGO1 facilitates the induction of genes in jasmonate (JA) signaling pathways and the activation of JA responses. Our findings suggest that, by binding and facilitating the expression of stimuli-specific genes, AGO1 may regulate diverse signaling pathways and associated biological processes.

Dietary flavonoids are poorly absorbed from the gastrointestinal tract. Colonic bacteria convert flavonoids into smaller phenolic acids (PA), which can be absorbed into the circulation and may contribute to the chemopreventive activity of the parent compounds. The purpose of our study was to determine whether flavonoids from green and black tea (GT, BT), citrus fruit with rutin (CF+R) and soy (S) supplements exposed to the same conditions in a dynamic in vitro model of the colon (TIM-2) will form the same phenolic acid products of microbial metabolism. About 600 mg of flavonoids from GT, BT, CF+R and S extracts were infused at t = 0 and 12 h into the TIM-2. Samples from the lumen and dialysate were collected at t = 0,4,8,12,16,24 and 28h. The flavonoid and PA concentrations were measured by HPLC and GC-MS. GT, BT, and CF+R formed 3-methoxy-4-hydroxyphenylacetic acid (3M4HPAA), 4-hydroxyphenyl acetic acid (4HPAA), 3,4-dihydroxyphenylacetic acid (3,4DHPAA), and 3-(3-hydroxyphenyl) propionic acid (3,3HPPA). BT flavonoids were also metabolized to 2,4,6-trihydroxybenzoic acid (2,4,6THBA) and CF+R flavonoids to 3-(4-hydroxy-3-methoxyphenyl) propionic acid (3,4H3MPPA), 3-hydroxyphenyl acetic acid (3HPAA) and a small amount of hippuric acid. After S infusion, we found 3M4HPAA and 4HPAA only. Among these phenolic acids, only 3,4DHPAA exhibited antiproliferative activity in prostate and colon cancer cells. 3,4DHPAA was significantly (P< 0.005) more inhibitory in colon cancer cells (HCT116) compared with an immortalized normal intestinal epithelial cell line (IEC6). In summary, fermentation by intestinal microbes of GT, BT, C+R, and S flavonoids resulted in the conversion to the same major phenolic acids.

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The altered ultrastructure and composition of cuticular wax from 'glossy Newhall' (MT) fruits lead to its glossy phenotype. A novel mutant derived from the wild-type (WT) 'Newhall' navel orange (Citrus sinensis [L.] Osbeck cv. Newhall), named 'glossy Newhall' (MT), which produced much more glossy fruits that were easily distinguishable from the WT fruits was characterized in this report. The total wax loads of both WT and MT fruits varied considerably during the fruit development. The most abundant wax fraction of WT mature fruits was triterpenoids, followed by aldehydes, alkanes, fatty acids, primary alcohol and cholesterol. The total wax load in MT mature fruits was reduced by 44.2 % compared with WT. Except for the minor wax components of primary alcohol and cholesterol, the amounts of all major wax fractions in MT mature fruits were decreased in varying degrees. The major reduction occurred in aldehydes that decreased 96.4 % and alkanes that decreased 81.9 %, which was consistent with scanning electron micrographs of MT mature fruit surfaces that showed a severe loss of wax crystals. Hence, aldehydes and alkanes were suggested to be required for wax crystal formation in 'Newhall' navel orange fruits.

Although both rhizome and root of Panax notoginseng are officially utilized as notoginseng in “Chinese Pharmacopoeia”, individual parts of the root were differently used in practice. To provide chemical evidence for the differentiated usage, quantitative comparison and metabolite profiling of different portions derived from the whole root, as well as commercial samples, were carried out, showing an overall higher content of saponins in rhizome, followed by main root, branch root, and fibrous root. Ginsenoside Rb2 was proposed as a potential marker with a content of 0.5 mg/g as a threshold value for differentiating rhizome from other parts. Multivariate analysis of the metabolite profile further suggested 32 saponins as potential markers for the discrimination of different parts of notoginseng. Collectively, the study provided comprehensive chemical evidence for the distinct usage of different parts of notoginseng and, hence, is of great importance for the rational application and exploitation of individual parts of notoginseng.