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• CUM reduced the initial biofilm production capacity and disrupt the three-dimensional architecture of S. aureus biofilm. • CUM inhibited cell motility, cell surface hydrophobicity and extracellular polymers production of S. aureus. • CUM interfered with the expression of adhesion genes associated with biofilm formation such as agrA, icaA, sigB, ebpS, fnbA, fib and clfA. • CUM bound to SarA by H-bonds to inhibit S. aureus biofilm. In Iranian, ethnopharmacological studies show that Cuminum cyminum is commonly used in pain relief. The most abundant component in C. cyminum seeds is cuminaldehyde (CUM). However, there are few articles that have evaluated the anti-biofilm activity against Staphylococcus aureus (S. aureus). The nobility of this study was to evaluate the anti-biofilm effect of CUM and to investigate its possible mechanism of action. Crystal violet staining assay showed that CUM decreased biofilm biomass. The morphological observation indicated that CUM restrained the adhesion of biofilm, and destroyed the integrated and cohesive structure of biofilm. MTT assay proved that the metabolic activity of adherent cells treated with CUM was reduced. In vitro assays exhibited that cell motility, cell surface hydrophobicity, and extracellular polymers production of S. aureus were also inhibited in the presence of CUM. Furthermore, quantitative real-time PCR analysis confirmed the ability of CUM to interfere with the expression of adhesion genes associated with biofilm formation such as agrA, icaA, sigB, ebpS, fnbA, fib and clfA. Molecular docking speculated that the interaction of CUM with SarA could inhibit SarA-DNA binding, and ultimately inhibit the formation of biofilm. The results of this trial provided scientific experimental data for the use of CUM as an anti-biofilm agent. [ABSTRACT FROM AUTHOR]

Abstract: Relative to mammals, the neuroendocrine control of pituitary growth hormone (GH) secretion and synthesis in teleost fish involves numerous stimulatory and inhibitory regulators, many of which are delivered to the somatotrophs via direct innervation. Among teleosts, how multifactorial regulation of somatotroph functions are mediated at the level of post-receptor signalling is best characterized in goldfish. Supplemented with recent findings, this review focuses on the known intracellular signal transduction mechanisms mediating the ligand- and function-specific actions in multifactorial control of GH release and synthesis, as well as basal GH secretion, in goldfish somatotrophs. These include membrane voltage-sensitive ion channels, Na+/H+ antiport, Ca2+ signalling, multiple pharmacologically distinct intracellular Ca2+ stores, cAMP/PKA, PKC, nitric oxide, cGMP, MEK/ERK and PI3K. Signalling pathways mediating the major neuroendocrine regulators of mammalian somatotrophs, as well as those in other major teleost study model systems are also briefly highlighted. Interestingly, unlike mammals, spontaneous action potential firings are not observed in goldfish somatotrophs in culture. Furthermore, three goldfish brain somatostatin forms directly affect pituitary GH secretion via ligand-specific actions on membrane ion channels and intracellular Ca2+ levels, as well as exert isoform-specific action on basal and stimulated GH mRNA expression, suggesting the importance of somatostatins other than somatostatin-14. [Copyright &y& Elsevier]

Grape (Vitis vinifera L.) berries are susceptible to quality deterioration after harvest. This study aimed to investigate the effect of folic acid (FA) treatment on the postharvest quality of table grape berries. Harvested 'Kyoho' (V. vinifera × V. labrusca L.) bunches were immersed in 1 mg L−1 FA solution for 15 min, then stored for sample collection and phenotype observation. Treatment with FA decreased the rates of berry abscission, water loss, and berry softening, reduced the accumulation of reactive oxygen species (ROS), and altered ROS metabolism-associated enzyme activities and gene expression levels. Transcriptome analysis revealed 507, 684, and 250 differentially expressed genes (DEGs) between FA-treated and non-treated berries at 3, 6, and 9 d after treatment, respectively. The DEGs were grouped into six modules according to a weighted correlation network analysis. A hub transcription factor, annotated as a WRKY transcription factor, was screened from the module associated with cell wall metabolism and identified as VvWRKY31. Transient transformation of grape berry slices revealed that overexpression of VvWRKY31 enhanced the relative expression level of VvRboh. The dual-luciferase assay showed that VvWRKY31 was capable of binding to VvRboh promoter. The present results provide insights into the potential molecular mechanism underlying FA-induced delay postharvest quality deterioration of grape berries. Specifically, FA inhibits expression of genes associated with ROS generation by reducing VvWRKY31 expression, thereby delaying quality deterioration induced by excessive accumulation of ROS. These results will be helpful in table grape breeding programs focused on delaying deterioration in postharvest quality. • Folic acid affects ROS metabolism in postharvest grape. • VvWRKY31 is a hub transcription factor in cell wall metabolism. • VvWRKY31 promotes VvRboh expression by binding its promoter. [ABSTRACT FROM AUTHOR]

• Grapevine plants were dwarfed by Chlormequat chloride (CCC). • Transcriptome data analysis showed that VviEXPA7 plays an important role. • The high expression of VviRAP2.12 transcription factor suppressed the expression of VviEXPA7 after CCC treatment, which led to the inhibition of cell elongation and plant dwarfing. Treatment with chlormequat chloride (CCC) can lead to dwarfism, which has been studied in many plants. However, the underlying molecular mechanisms have been less studied. Herein, the phenotypic changes and gene expression levels of grapevine in response to CCC were investigated. Results showed that the height of grape plants became significantly shorter after CCC treatment, especially between the first two stems above the roots. Transcriptome sequencing was then performed and analyzed, 120 differentially expressed genes (DEGs) were detected in the stems after CCC treatment compared to the control. The gene ontology (GO) enrichment results showed that processes such as cellulose synthase (UDP-forming) activity, regulation of the auxin-mediated signaling pathway, and the cellulose biosynthetic process were common. In addition, weighted gene co-expression network analysis (WGCNA) identified the strong correlation between the MEbrown module and stem development. VviEXAP7 was selected from the genes belonging to key GO pathways and WGCNA modules. The quantitative real-time PCR (qRT-PCR) results showed that VviEXPA7 was significantly downregulated because of the CCC treatment. Additionally, analysis of VviEXPA7 promoter activity showed that VviEXPA7 activated GUS gene expression, and was induced by CCC, abscisic acid (ABA), and other hormones. VviEXPA7 was used as a target gene for transcription factor prediction, and after employing the PlantTFDB and JASPAR databases, VviRAP2.12 was identified as a transcription factor that might regulate VviEXPA7. qRT-PCR revealed that VviRAP2.12 was significantly upregulated after CCC treatment. Finally, the interaction between VviEXPA7 and VviRAP2.12 was verified by the dual-luciferase assay. Thus, the current study shows that CCC decreased the expression of the cell growth-related gene VviEXPA7 by promoting the expression of VviRAP2.12, which resulted in dwarfed plants. This study generated new information that will increase our understanding of the mechanism of action of CCC and provides a scientific basis for simplified cultivation of grapes. [ABSTRACT FROM AUTHOR]

• Six genes are determined as proline biosynthesis- or proline catabolism-related genes in grapevines. • P5CS1, OAT, PDH and P5CDH can be significantly induced by osmotic and oxidative stresses. • Proline is greatly accumulated under abiotic stresses, especially osmotic and oxidative stresses. • Proline biosynthesis and proline catabolism-related genes synergistically regulate proline accumulation in response to abiotic stresses. Proline is an important osmotic regulator for plants under abiotic stresses. Proline accumulation is regulated by various enzymes, while genes encoding these enzymes have not been fully investigated in grapevines. In this study, we identified four proline biosynthesis-related genes (P5CS1, P5CS2, P5CR and OAT) and two proline catabolism-related genes (PDH and P5CDH) from grapevines, and conducted bioinformatics analysis including protein characteristic, gene structure, phylogenetic relationship and cis-acting element of promoters. Promoter analysis found that cis-acting elements related to stress and phytohormone responsiveness were present in the promoters of these genes. Tissue-specific expression analysis of these genes indicated that P5CS2, OAT and PDH expressed highly in flower, and P5CS1, P5CR and P5CDH had highest expression levels in tendril, berry and leaf respectively. Expression patterns of these genes under abiotic stresses revealed that P5CS1, OAT and PDH could be significantly induced by salt, dehydration, PEG and H 2 O 2 treatments, and P5CDH was significantly suppressed under these stress treatments. By measuring proline accumulation in grapevines, we found that proline content dramatically increased after treatments of salt, dehydration, PEG and H 2 O 2. Our results revealed the molecular responses (especially P5CS1, OAT, PDH and P5CDH) in the proline metabolism pathway to osmotic and oxidative stresses in grapevines, demonstrating that proline synthesis and proline catabolism synergistically regulate proline accumulation in response to abiotic stresses. [ABSTRACT FROM AUTHOR]

Abstract: Holomycin is a dithiolopyrrolone antibiotic natural product produced by Streptomyces clavuligerus, ATCC 27064. This paper reports on the identification of a gene cluster from S. clavuligerus that directs holomycin biosynthesis. Heterologous expression of the cluster in S. albus then induced the production of holomycin. Bioinformatics analysis of the gene cluster revealed that holomycin was assembled by a single multidomain non-ribosomal peptide synthetase (NRPS) consisting of heterocyclization, adenylation, and thiolation domains (Cy-A-T), a free-standing condensation domain, two thioesterases, five tailoring enzymes involved in oxidative reactions and two regulatory and transcriptional genes. Knock out of the gene, HomI, completely abolished the production of holomycin, which is consistent with its role as a key biosynthetic gene and is likely involved in the formation of the disulfide bond generating the final precursor, holothin. [Copyright &y& Elsevier]

Abstract: Schistosomiasis japonica is currently one of the most serious parasitic diseases and over 670000 people are infected in China by the end of 2006. In order to establish an effective diagnostic method, the gene coding for Sj14-3-3 and Sj26kDa GST were cloned and expressed separately in Escherichia coli as fusion protein with His-tag. The rSj14-3-3 and 26kDa rSjGST were combinedly used as antigens for enzyme-linked immunosorbent assays (ELISA) to diagnose acute and chronic S. japonica. Our results showed that the sensitivity in diagnoses of both acute and chronic schistosomiasis was 94.4% (67/71) and 80.7% (96/119), respectively. The specificity was 94.7% applying 132 sera from people living in S. japonicum-free areas. The data also showed that the recombinant proteins cross-react with Clonorchis sinensis and hookworms at a rate of 11.8% and 5.3% respectively. Parallel tests were conducted among ELISA, indirect hemagglutination assay (IHA) and circular ovum precipitin test (COPT) to determine anti-S. japonicum antibodies in sera of patients with schistosomiasis, healthy control, and those infected with other parasites and the results showed no significant difference in sensitivity for acute schistosomiasis between ELISA and IHA assays (χ 2 =1.33, P >0.05), but significant between ELISA and COPT assays (χ 2 =6.72, P <0.01). Our results also revealed significant difference in positive rate between ELISA and IHA (χ 2 =24.74, P <0.005), as well as between ELISA and COPT (χ 2 =58.14, P <0.005). These results suggest that the rSj14-3-3 and r26kDa SjGST would be effective diagnostic antigens for detection of antibodies to S. japonicum in human. Due to the easy production, high sensitivity and specificity, the recombinant proteins tested in this study can be considered as candidate reagent for immunological diagnosis of human schistosomiasis. [Copyright &y& Elsevier]