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Here, we report characterization of an RbcS promoter and its transit peptide for use in chloroplast-targeted expression. RbcS3 that encodes a small subunit of ribulose bisphosphate carboxylase/oxygenase is of great interest due to its green tissue-specific expression such as leaf and leaf sheaths. We isolated the RbcS3 promoter and its transit peptide sequence and linked to GFP for characterization in transgenic plants. Our qRT-PCR analysis on leaves and roots of transgenic plants revealed that GFP transcript levels were higher by fivefold in leaves of RbcS3:TP3:GFP transgenic lines than in those of the RbcS3:GFP transgenic lines, suggesting that the transcript levels were increased by chloroplast-targeted expression, as shown in previously characterized RbcS1:TP1 system. The transit peptide sequence TP3 was sufficient to target GFP to chloroplasts as observed in protoplasts of RbcS3:TP3:GFP transgenic lines. GFP fluorescence in RbcS3:GFP plants was detected only in the cytosol. The GFP protein levels in leaves of RbcS3:TP3:GFP plants were 0.12-0.23 % of the total soluble leaf proteins. These levels were higher or comparable to those of PGD1:GFP plants ( GFP driven by a constitutive promoter PGD1). Taken together, these results indicate that the fusion of the RbcS3 promoter to its transit peptide, RbcS3:TP3, provides a chloroplast-targeting expression system. [ABSTRACT FROM AUTHOR]

Main conclusion: We have characterized four novel constitutive promoters ARP1, H3F3, HSP and H2BF3 that are active in all tissues/stages of transgenic plants and stable over two homozygous generations. Gene promoters that are active and stable over several generations in transgenic plants are valuable tools for plant research and biotechnology. In this study, we characterized four putative constitutive promoters ( ARP1, H3F3, HSP and H2BF3) in transgenic rice plants. Promoter regions were fused to the green fluorescence protein (GFP) reporter gene and transformed into rice. Single-copy transgenic lines were then selected and promoter activity was analyzed in various organs and tissues of two successive homozygous generations. All four promoters showed a broad expression profile in most tissues and developmental stages, and indeed the expression of the ARP1 and H3F3 promoters was even greater than that of the PGD1 promoter, a previously described constitutive promoter that has been used in transgenic rice. This observation was based on expression levels in leaves, roots, dry seeds and flowers in both the T and T generations. Each promoter exhibited comparable levels of activity over two homozygous generations with no sign of transgene silencing, which is an important characteristic of promoters to be used in crop biotechnology applications. These promoters therefore have considerable potential value for the stable and constitutive expression of transgenes in monocotyledonous crops. [ABSTRACT FROM AUTHOR]

Many stress-inducible genes including the transcription factor basic leucine zipper (bZIP) are involved in the response of plants to environmental stresses. bZIPs are composed of two domains, a basic region for DNA binding and a leucine zipper region for dimerization. In this study, two drought-induced bZIP genes OsbZIP23 and OsbZIP45 were identified in rice. The transcription factors are orthologs of Arabidopsis bZIPs belonging to groups A and G, respectively, and are known to be involved in drought tolerance. To investigate the regulation of OsbZIP23 and OsbZIP45 expression in rice, quantitative RT-PCR was performed using RNAs from plants grown at drought stress conditions and different developmental stages. Expression of OsbZIP23 and OsbZIP45 showed positive correlation with drought tolerance. To further understand the functions of OsbZIP23 and OsbZIP45, we overexpressed OsbZIP23 and OsbZIP45 in rice using PGD1 promoter. Results of phenotypic and chlorophyll fluorescence analysis on PGD1: OsbZIP23 and PGD1: OsbZIP45 plants showed enhanced tolerance to drought stress. These results suggest that OsbZIP23 and OsbZIP45 are involved in drought stress response in rice and have a great potential for engineering drought-tolerant crops. [ABSTRACT FROM AUTHOR]

We investigated whether aqueous extract of the root of Platycodon grandiflorum A. de Candolle (APG), platycodinD3 and deapi-platycodin significantly affect the production and secretion of airway mucin using in vivo and in vitro experimental models. Effect of APG was checked on hypersecretion of pulmonary mucin in sulfur dioxide-induced bronchitis in rats. Confluent NCI-H292 cells were pretreated with platycodinD3 or deapi-platycodin for 30min and then stimulated with PMA (phorbol 12-myristate 13-acetate) for 24h. The MUC5AC mucin production and secretion were measured by ELISA. The results were as follows: (1) APG stimulated the secretion of airway mucin in sulfur dioxide-induced bronchitis rat model; (2) platycodinD3 and deapi-platycodin inhibited the production of MUC5AC mucin induced by PMA from NCI-H292 cells, respectively; (3) however, platycodinD3 and deapi-platycodin did not inhibit but stimulated the secretion of MUC5AC mucin induced by PMA from NCI-H292 cells, respectively. This result suggests that aqueous extract of P. grandiflorum A. de Candolle and the two natural products derived from it, platycodinD3 and deapi-platycodin, can regulate the production and secretion of airway mucin and, at least in part, explains the traditional use of aqueous extract of P. grandiflorum A. de Candolle as expectorants in diverse inflammatory pulmonary diseases. [ABSTRACT FROM AUTHOR]

Abstract: We investigated whether aqueous extract of the root of Platycodon grandiflorum A. de Candolle (APG), platycodinD3 and deapi-platycodin significantly affect the production and secretion of airway mucin using in vivo and in vitro experimental models. Effect of APG was checked on hypersecretion of pulmonary mucin in sulfur dioxide-induced bronchitis in rats. Confluent NCI-H292 cells were pretreated with platycodinD3 or deapi-platycodin for 30min and then stimulated with PMA (phorbol 12-myristate 13-acetate) for 24h. The MUC5AC mucin production and secretion were measured by ELISA. The results were as follows: (1) APG stimulated the secretion of airway mucin in sulfur dioxide-induced bronchitis rat model; (2) platycodinD3 and deapi-platycodin inhibited the production of MUC5AC mucin induced by PMA from NCI-H292 cells, respectively; (3) however, platycodinD3 and deapi-platycodin did not inhibit but stimulated the secretion of MUC5AC mucin induced by PMA from NCI-H292 cells, respectively. This result suggests that aqueous extract of P. grandiflorum A. de Candolle and the two natural products derived from it, platycodinD3 and deapi-platycodin, can regulate the production and secretion of airway mucin and, at least in part, explains the traditional use of aqueous extract of P. grandiflorum A. de Candolle as expectorants in diverse inflammatory pulmonary diseases. [Copyright &y& Elsevier]

Abstract: In the present study, we investigated whether aqueous extract of Liriope Tuber, ophiopogonin D and spicatoside A derived from Liriope Tuber affect basal or phorbol ester (phorbol 12-myristate 13-acetate, PMA)-induced airway mucin production and secretion from airway epithelial cells. Confluent NCI-H292 cells were treated with each agent for 24h (basal production) or pretreated with each agent for 30min and then stimulated with PMA for 24h (PMA-induced production and secretion), respectively. MUC5AC airway mucin production and secretion were measured by ELISA. The results were as follows: (1) aqueous extract of Liriope Tuber stimulated basal mucin production and did not inhibit but increased PMA-induced mucin production; (2) ophiopogonin D and spicatoside A stimulated basal mucin production and did not inhibit but increased PMA-induced mucin production; (3) two compounds increased PMA-induced mucin secretion. These results suggest that ophiopogonin D and spicatoside A can increase mucin production and secretion, by directly acting on airway epithelial cells and, at least in part, explain the traditional use of aqueous extract of Liriope Tuber as expectorants in diverse inflammatory pulmonary diseases. [Copyright &y& Elsevier]

In this study, we investigated whether wogonin significantly affects MUC5AC mucin gene expression and production in human airway epithelial cells. Confluent NCI-H292 cells were pretreated with wogonin for 30 min and then stimulated with tumor necrosis factor-α (TNF-α) for 24 h or the indicated periods. The MUC5AC mucin gene expression and mucin protein production were measured by RT-PCR and ELISA, respectively. We found that incubation of NCI-H292 cells with wogonin significantly inhibited mucin production and down-regulated MUC5AC gene expression induced by TNF-α in a dose-dependent fashion. To elucidate the action mechanism of wogonin, effect of wogonin on TNF-α-induced NF-κB signaling pathway was investigated by western blot analysis. Wogonin inhibited NF-κB activation induced by TNF-α. Inhibition of IKK by wogonin led to the suppression of IκB phosphorylation and degradation, p65 nuclear translocation and NF-κB-regulated gene expression. This, in turn, led to the down-regulation of MUC5AC protein production in NCI-H292 cells. Wogonin also inhibited the gene products involved in cell survival (Bcl-2) and proliferation (cyclooxygenase-2). These results suggest that wogonin inhibits the NF-κB signaling pathway, which may explain its role in the inhibition of MUC5AC mucin gene expression and production. [ABSTRACT FROM AUTHOR]

To investigate a) daily patterns of park use, leisure-time physical activity and stress, b) relationship of daily park use and leisure-time physical activity with stress; and c) the combined effects of daily park use and leisure-time physical activity on stress, and whether associations of daily park use and leisure-time physical activity with stress are independent. Singapore citizens/permanent residents 21-75 years-of-age from the Multi-Ethnic Cohort were enrolled into this study. Participants received mobile Ecological Momentary Assessment (mEMA) mini-surveys for up to nine days via their smartphone, with daily questions on park use and leisure-time physical activity, and perceived stress level in the evening. Descriptive statistics summarized demographics, day-to-day variation in park use, leisure-time physical activity and stress. Logistic regression models using generalized estimating equations assessed relationships of daily park use and leisure time physical activity with stress. A total of 605 participants providing 4678 EMA responses to mini-surveys were included in the analyses. Participants who visited parks during a day were less stressed on the same evening than those who did not visit parks (OR = 0.67; 95% CI = 0.58–0.77). Likewise, participants who were physically active during a day were less stressed on the same evening than those who were not physically active (OR = 0.73; 95% CI = 0.64–0.82). Daily park use and leisure-time physical activity on the same day was also associated with less stress (OR = 0.58; 95% CI = 0.49–0.69), and this measure of association was lower than those comparing daily engagement in only 1 of the 2 activities. The effects of park use and physical activity on lower perceived stress were independent. Both daily park use and leisure time physical activity during the day were associated with reduced evening stress. These relationships were independent of one another, suggesting that each activity on its own is beneficial to reducing stress amongst adults in urban settings. • Studies investigating association of park use and physical activity with stress are rare. • This study used ecological momentary assessment methods. • Daily park use and leisure-time physical activity were independently associated with lower stress. • The combination of reporting park use and leisure-time physical activity was associated with lower stress than either alone. • Health promotion strategies could target both park visitation and physical activity within parks. [ABSTRACT FROM AUTHOR]

Gene promoter(s) specialized in root tissues is an important component for crop biotechnology. In our current study, we report results of promoter analysis of the HPX1, a gene expressed predominantly in roots. The HPX1 promoter regions were predicted, linked to the gfp reporter gene, and transformed into rice. Promoter activities were analyzed in various organs and tissues of six independent transgenic HPX1:gfp plants using the fluorescent microscopy and q-RT-PCR methods. GFP fluorescence levels were high in root elongation regions but not in root apex and cap of the HPX1:gfp plants. Very low levels of GFP fluorescence were observed in anthers and leaves. Levels of promoter activities were 16- to 190-fold higher in roots than in leaves of the HPX1:gfp plants. The HPX1 promoter directs high levels of gene expression in root tissues producing GFP levels up to 0.39 % of the total soluble protein. Thus, the HPX1 promoter is predominantly active in the root elongation region during the vegetative stage of growth. [ABSTRACT FROM AUTHOR]