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Acidovorax citrulli can cause bacterial fruit blotch of watermelon, melon, and other cucurbits, and has the potential to cause severe economic losses to growers throughout the world. This article investigated the functions and interactions of the pilR and pilS genes, two important genes in bacterial type IV pili systems, in A. citrulli. For each gene, deletion mutants and complementary strains were constructed via homologous recombination, and their phenotypes were determined. The results showed that the absence of pilR and pilS could significantly reduce the pathogenicity and twitching motility of A. citrulli while increasing the swimming motility, biofilm formation, and in vitro growth. Conversely, complementary strains were no different than the wild-type strain. Using quantitative reverse transcription PCR and promoter activity assays, we confirmed that the deletion of pilR and pilS genes leads to a significant decrease in the transcription level of pilA. Meanwhile, three methods including yeast two-hybrid, glutathione S-transferase pull-down, and luciferase complementation imaging assays were used to verify the direct interaction between the PilR and PilS proteins. These findings revealed the biological function of the pilR and pilS and confirms their regulatory role on pilA. [ABSTRACT FROM AUTHOR]

Aphids exhibit wing polyphenism. Winged and wingless aphid morphs are produced by parthenogenesis depending on population density and host plant quality. Recent studies showed that microRNAs in alate and apterous individuals have differential expression and are involved in wing dimorphism of Acyrthosiphon pisum. From which miR-92a-1-p5 can target the mRNA of flight muscle gene flightin in vitro, but what effect they have on wing development of aphid is unclear. Here with the nanocarrier-delivered RNA interference (RNAi) method, flightin gene was knocked down in winged nymphs of A. pisum. Results showed that the majority (63.33%) of adults had malformed wings, the shape of dorsal longitudinal muscle (DLM) was deformed severely, the dorsoventral flight muscle (DVM) became wider and looser in aphids with flightin reduction compared with the negative control. Overexpression of miR-92a-1-p5 caused decreased expression of flightin and malformed wings of aphids, with a mutant ratio of 62.50%. Morphological analysis of flight musculature showed the consistent result as that with flightin knockdown. These results suggest that flightin is essential for flight musculature formation and wing extension in A. pisum , which can be modulated by miR-92a-1-p5. [ABSTRACT FROM AUTHOR]

Background: Studies have shown that the high incidence of type 2 diabetes in China is associated with low birth weight and excessive nutrition in adulthood, which occurred during the famine years of the 1950s and 1960s, though the specific molecular mechanisms are unclear. In this study, we proposed a severe maternal caloric restriction during late pregnancy, followed by a post weaning high-fat diet in mice. After weaning, normal and high-fat diets were provided to mice to simulate the dietary pattern of modern society. Methods: The pregnant mice were divided into two groups: normal birth weight (NBW) group and low birth weight (LBW) group. After 3 weeks for weaning, the male offspring mice in the NBW and LBW groups were then randomly divided into four subgroups: NC, NH, LC and LC groups. The offspring mice in the NC, NH, LC and LC groups were respectively fed with normal diet, normal diet, high-fat diet and high-fat diet for 18 weeks. After 18 weeks of dietary intervention, detailed analyses of mRNA and protein expression patterns, signaling pathway activities, and promoter methylation states were conducted for all relevant genes. Results: After dietary intervention for 18 weeks, the expressions of CD36, Fabp4, PPARγ, FAS, and ACC1 in the skeletal muscle tissue of the LH group were significantly increased compared with the LC and NH groups (P < 0.05). The level of p-AMPK/AMPK in the skeletal muscle tissue of the LH group was significantly decreased compared with the LC and NH groups (P < 0.05). CPT1 and PGC-1α protein expressions were up-regulated in the LH group (P < 0.05) compared to the LC group. Additionally, the DNA methylation levels of the PGC-1α and GLUT4 gene promoters in the skeletal muscle of the LH groups were higher than those of the LC and NH groups (P < 0.05). However, PPARγ DNA methylation level in the LH group was lower than those of the LC and NH groups (P < 0.05). Conclusions: LBW combined with high-fat diets may increase insulin resistance and diabetes through regulating the CD36-related Fabp4-PPARγ and AMPK/ACC signaling pathways. [ABSTRACT FROM AUTHOR]

Abstract Desmocollin 3 (DSC3) is a transmembrane adhesion protein of desmosomes and involved in carcinogenesis in various cancer types. Downregulation of DSC3 has been reported in colorectal cancer (CRC). However, the function of DSC3 in CRC has not yet been elucidated. In this study, we performed cell-based functional analysis after DSC3 overexpression by stable transfection and knockdown by siRNA in CRC cells. It turned out that overexpression of DSC3 reduced cell proliferation, colony forming ability, induced G0/G1 cell cycle arrest and promoted apoptosis. Further pathway analysis showed that overexpression of DSC3 significantly inhibited the activity of AKT pathway and increased the expression of E-cadherin as well as p53 and p21. In contrast, siRNA-mediated knockdown of DSC3 increased cell proliferation and colony formation, activated the AKT pathway and decreased the expression of E-cadherin as well as p53 and p21. Additionally, in primary CRC patient samples, the expression of DSC3 protein was significantly related to the expression of desmocollin 1 (DSC1) and desmocollin 2 (DSC2) as well as E-cadherin (p < 0.001 respectively). Taken together, our data reveal that DSC3 suppresses CRC cell growth through inhibition of AKT pathway and regulation of E-cadherin. DSC3 may serve as a novel therapeutic target for CRC. Highlights • Desmocollin 3 inhibits colorectal carcinoma cell proliferation, induces cell cycle arrest and enhances apoptosis. • Desmocollin 3 acts as a tumor suppressor through inhibition of Akt pathway and regulation of E-cadherin. • Desmocollin 3 expression is correlated to desmocollin 1 and 2 as well as E-cadherin in primary colorectal carcinoma. [ABSTRACT FROM AUTHOR]

Desmosomes are intercellular junctions that confer strong cell–cell adhesion. Altered expression of desmocollin 3 (DSC3), a member of the desmosomal cadherin family, was found in various cancers; however, its functional involvement in carcinogenesis has not yet been elucidated. Expression/localization of DSC3 was analyzed by real-time reverse transcription–PCR, western blotting, immunofluorescence and immunohistochemistry. Methylation status of DSC3 was examined by demethylation tests, methylation-specific PCR and bisulfite sequencing. It turned out that downregulation of DSC3 in lung cancer cells was associated with DNA hypermethylation. In primary lung tumors, DSC3 was a potential diagnostic marker for lung squamous cell carcinoma, and DSC3 DNA hypermethylation was correlated with poor clinical outcome. To investigate the effect of the tumor suppressor gene p53 on DSC3, transient transfection with a wild-type p53-expression vector was performed. Overexpression of p53 resulted in an increased expression of DSC3 in a DSC3-unmethylated lung cancer cell line H2170, but not in H1299, a DSC3-methylated cell line. However, combination of p53 transfection with demethylation agent 5-aza-2ʹ-deoxycytidine treatment led to increased expression of DSC3 in H1299 cells. Furthermore, functional studies after stable transfection of a DSC3 expression vector showed that ectopic expression of DSC3 inhibited cell proliferation, anchorage-independent growth, migration, as well as invasion, and most interestingly led to reduced phosphorylation levels of extracellular signal-regulated kinase1/2. Taken together, our data suggested that DSC3 acts as a novel tumor suppressor gene through inhibition of epidermal growth factor receptor/extracellular signal-regulated kinase signaling in lung cancer cells. [ABSTRACT FROM PUBLISHER]

Finding new applications for existing pharmaceuticals, known as drug repositioning, is a validated strategy for resolving the problem of high expenditure but low productivity in drug discovery. Currently, the prevalent computational methods for drug repositioning are focused mainly on the similarity or relevance between known drugs based on their 'features', including chemical structure, side effects, gene expression profile, and/or chemical-protein interactome. However, such drug-oriented methods may constrain the newly predicted functions to the pharmacological functional space of the existing drugs. Clinically, many drugs have been found to bind 'off-target' (i.e. to receptors other than their primary targets), which can lead to undesirable effects. In this study, which integrates known drug target information, we propose a disease-oriented strategy for evaluating the relationship between drugs and disease based on their pathway profile. The basic hypothesis of this method is that drugs exerting a therapeutic effect may not only directly target the disease-related proteins but also modulate the pathways involved in the pathological process. Upon testing eight of the global best-selling drugs in 2010 (each with more than three targets), the FDA (Food and Drug Administration, USA)-approved therapeutic function of each was included in the top 10 predicted indications. On average, 60% of predicted results made using our method are proved by literature. This approach could be used to complement existing methods and may provide a new perspective in drug repositioning and side effect evaluation. [ABSTRACT FROM AUTHOR]

Panax ginseng C.A. Meyer is one of the most important medicinal plants in Northeast China, and ginsenosides are the main active ingredients found in medicinal ginseng. The biosynthesis of ginsenosides is regulated by environmental factors and the expression of key enzyme genes. Therefore, in this experiment, ginseng in the leaf opened stage, the green fruit stage, the red fruit stage, and the root growth stage was used as the test material, and nine individual ginsenosides and total saponins (the sum of the individual saponins) were detected by HPLC (High Performance Liquid Chromatography). There was a trend of synergistic increase and decrease, and saponin accumulation and transfer in different tissues. The expression of key enzyme genes in nine synthetic pathways was detected by real-time PCR, and the correlation between saponin content, gene expression, and ecological factors was analyzed. Correlation analysis showed that in root tissue, PAR (Photosynthetically Active Radiation) and soil water potential had a greater impact on ginsenoside accumulation, while in leaf tissue, temperature and relative humidity had a greater impact on ginsenoside accumulation. The results provide a theoretical basis for elucidating the relationship between ecological factors and genetic factors and their impact on the quality of medicinal materials. The results also have guiding significance for realizing the quality of medicinal materials. [ABSTRACT FROM AUTHOR]

Abstract: Insulin-like growth factor binding protein 7 (IGFBP7) was considered a tumor suppressor gene in lung cancer. However, the mechanism responsible for the downregulation of this gene has not yet been fully understood. In this study, we analyzed the epigenetic inactivation of IGFBP7 expression in human lung cancer. We found that 14 out of 16 lung cancer cell lines showed decreased expression of IGFBP7 compared to control cells by real-time RT-PCR, and 42 out of 90 patients (46.7%) with primary lung tumor exhibited negative staining of IGFBP7 by immunohistochemistry analysis. The IGFBP7 expression could be restored by demethylation agent 5-aza-2′-deoxycytidine (DAC) in 7 cancer cell lines. Methylation status of IGFBP7 was further evaluated by bisulfite sequencing (BS) and methylation-specific-PCR (MSP). It turned out that low expression of IGFBP7 was associated with DNA methylation in lung cancer cell lines and in primary lung tumors (P =0.019). To explore the regulatory role of p53 on IGFBP7, we transfected a wild type p53 expression vector into lung cancer cell lines H1299, H2228, and H82. Forced expression of p53 increased IGFBP7 expression only in H82 harboring no IGFBP7 methylation, while transfection in combination with DAC induced the expression of IGFBP7 in H1299 and H2228, in which IGFBP7 was methylated. Additionally, treatment with p53 inducer adriamycin (ADR) alone or in combination with DAC increased the expression of IGFBP7 in the 3 cell lines. Our data suggest that IGFBP7 is inactivated in lung cancer by DNA hypermethylation in both lung cancer cell lines and primary lung tumors, and IGFBP7 might be regulated by p53 in lung cancer cells. [Copyright &y& Elsevier]