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Telomeric DNA and C-myc22 are DNA G-quadruplex (G4)-forming sequences associated with tumorigenesis. Ligands that can facilitate the formation and increase the stabilization of G4 can halt tumor cell proliferation and have been regarded as potential anti-cancer drugs. In the present study, we have investigated the interaction of 11 natural alkaloids with G4 formed by telomeric DNA and C-myc22 sequences. Our results indicated that sanguinarine (San), palmatine (Pal), and berberine (Beb) of the first series (S1) can induce the formation of G4 as well as increase the stabilization ability. Daurisoline (S2-1), O-methyldauricine (S2-2), O-diacetyldaurisoline (S2-3), daurinoline (S2-4), dauricinoline (S2-5), N,N'-dimethyldauricine iodide (S2-6), and N,N'-dimethyldaurisoline iodide (S2-7) of the second series (S2) showed similar stabilization ability. We found that unsaturated ring C, N(+) positively charged centers, and conjugated aromatic rings are key factors to increase the stabilization ability of S1, and we gave some advice on structure modification to S2 through structure-activity study. Besides, we found San and Pal to be cell cycle blocker in G(1). San was speculated to bind to G4 through intercalation or end stacking.

RNA/DNA sequences rich in guanine (G) can form a 4-strand structure, G-quadruplex, which has been extensively researched and observed in mammalian, fungi, and plants, with in vivo existence in eukaryotic cells. Compared with DNA quadruplex, the potential existence of RNA quadruplex appears to be generally rare; however, it is believed by some researchers to be more inevitable in vivo and speculated to play an important role where it exists. Recently, researches concerning the function of G-quadruplexes in RNAs commence, making much progress. However, there is no available review particularly focusing on RNA quadruplex till now as we know. Therefore, we decide to give a review to comprehensively summarize research progress on it. This review highlights the diverse topologies for RNA quadruplex structure and its effect factors; outlines the current knowledge of RNA quadruplex's physiological functions in biological systems, especially in gene expression; and presents the prospects of RNA quadruplex.

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A range of Ru-, Rh-, or Pd-catalyzed vinylic C–H/C–H cross-coupling reactions of olefins have been demonstrated to provide 1,3-dienes, using a quantitative amount of metal oxidants. Although transfer hydrogenation and C–H alkenylation are two important areas that evolved independently, we herein report the first iridium-catalyzed cross-coupling reactions of alkenes by integration of directed C­(alkenyl)–H alkenylation and transfer hydrogenation to obviate the usage of a metal oxidant, employing a hydrogen acceptor such as inexpensive chloranil.

Sucrose synthase (SuSy) is considered the first key enzyme for secondary growth because it is a highly regulated cytosolic enzyme that catalyzes the reversible conversion of sucrose and UDP into UDP-glucose and fructose. Although SuSy enzymes preferentially functions in the direction of sucrose cleavage at most cellular condition, they also catalyze the synthetic reaction. We isolated a gene that encodes a SuSy from Populus simonii×Populus nigra and named it PsnSuSy2 because it shares high similarity to SuSy2 in Populus trichocarpa. RT-PCR revealed that PsnSuSy2 was highly expressed in xylem, but lowly expressed in young leaves. To characterize its functions in secondary growth, multiple tobacco overexpression transgenic lines of PnsSuSy2 were generated via Agrobacterium-mediated transformation. The PsnSuSy2 expression levels and altered wood properties in stem segments from the different transgenic lines were carefully characterized. The results demonstrated that the levels of PsnSuSy2 enzyme activity, chlorophyll content, total soluble sugars, fructose and glucose increased significantly, while the sucrose level decreased significantly. Consequently, the cellulose content and fiber length increased, whereas the lignin content decreased, suggesting that PsnSuSy2 plays a significant role in cleaving sucrose into UDP-glucose and fructose to facilitate cellulose biosynthesis and that promotion of cellulose biosynthesis suppresses lignin biosynthesis. Additionally, the noticeable increase in the lodging resistance in transgenic tobacco stem suggested that the cell wall characteristics were altered by PsnSuSy2 overexpression. Scanning electron microscopy was performed to study the cell wall morphology of stem, and surprisingly, we found that the secondary cell wall was significantly thicker in transgenic tobacco. However, the thickened secondary cell wall did not negatively affect the height of the plants because the PsnSuSy2- overexpressing lines grew taller than the wildtype plants. This systematic analysis demonstrated that PsnSuSy2 plays an important role in cleaving sucrose coupled with cellulose biosynthesis in wood tissue.

The selection of fresh product suppliers is a multi-criteria decision making (MCDM) problem with great significant and application value. This requires trade-offs between multiple criteria to prove its ambiguity and uncertainty. Therefore, a novel two-stage fuzzy integrated MCDM method to select suitable suppliers is employed. In the first stage, two collective relationship matrixes are constructed by quality function development (QFD), and relationships among customer requirements (CRs), company strategies (CSs) as well as selection criteria are considered separately in the two matrixes. Subjective criteria weights are obtained by fuzzy best-worst method (BWM) appropriately. In the second stage, the objective criteria weights are obtained using Shannon's entropy method, and the fuzzy multi-objective optimization by ratio analysis plus the full multiplicative form (MULTIMOORA) is applied to rank suppliers. Finally, an application case is applied to prove the feasibility of the proposed method. These conclusions can help companies improve their CSs and increase their market competitiveness.

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