Search

Fungal diseases such as the devastating rice blast pose severe threats to crop production worldwide. Biological control of crop diseases caused by fungal pathogens is an environment-friendly approach for safeguarding crop production. But the insufficient availability of microbial agents effective against various fungal diseases has hampered the development of green production in crops. In this study, we identified a broad-spectrum antifungal bacterium, Streptomyces graminearus STR-1, showing antagonistic activity to diverse fungal pathogens including Magnaporthe oryzae, Rhizoctonia solani, Fusarium graminearum, Ustilaginoidea virens, and Bipolaris maydis. Its antifungal activity was relatively stable and less affected by temperature and pH. Evaluation of the biocontrol activity of STR-1 revealed that STR-1 prevented and controlled rice blast disease via eliciting plant immunity and suppressing fungal infectionstructure development. STR-1 broth extract inhibited spore germination, likely through inhibiting protein synthesis. Combining LC-MS and chromatography analysis of the antimicrobial compounds purified from STR-1 broth extract, together with decoding STR-1 genomic sequence, we identified 4-oxo-4-[(1-phenylethyl)amino]but-2-enoic acid, 1,3,5-Trimethylpyrazole and SMA-1 as the potential main STR-1 secondary metabolites associated with its antifungal effects. This study suggests that bacterial strain STR-1 could be used for identifying highly effective and broad-spectrum secondary metabolites for containing rice blast and other crop diseases. The application of the active compounds offers a promising measure to tackle fungal disease. [ABSTRACT FROM AUTHOR]

Objective: Most brain function assessments for disorders of consciousness (DOC) utilized quantified characteristics, measured only once, ignoring the variation of patients' brain states. The study aims to investigate the brain activities of patients with DOC from a new perspective: variability of a large timescale functional network. Methods: Forty-nine patients were enrolled in this study and performed a 1-week behavioral assessment. Subsequently, each patient received electroencephalography (EEG) recordings five times daily at 2-h intervals. Functional connectivity and networks were measured by weighted phase lag index and complex network parameters (characteristic path length, cluster coefficient, and betweenness centrality). The relative coefficient of variation (CV) of network parameters was measured to evaluate functional network variability. Results: Functional networks of patients with vegetative state/unresponsive wakefulness syndrome (VS/UWS) showed significantly higher segregation (characteristic path length) and lower centrality (betweenness centrality) than emerging fromtheminimal conscious state (EMCS) andminimal conscious state (MCS), as well as lower integration (cluster coefficient) than MCS. The functional networks of VS/UWS patients consistently presented the highest variability in segregation and integration (i.e., highest CV values of characteristic path length and cluster coefficient) on a larger time scale than MCS and EMCS. Moreover, the CV values of characteristic path length and cluster coefficient showed a significant inverse correlation with the Coma Recovery Scale-Revised scores (CRS-R). The CV values of network betweenness centrality, particularly of the cento-parietal region, showed a positive correlation with the CRS-R. Conclusion: The functional networks of VS/UWS patients present the most invariant segregation and integration but divergent centrality on the large time scale networks than MCS and EMCS. Significance: The variations observed within large timescale functional networks significantly correlate with the degree of consciousness impairment. This finding augments our understanding of the neurophysiological mechanisms underpinning disorders of consciousness. [ABSTRACT FROM AUTHOR]

Introduction: Cloud fitness is transforming indoor exercise for young people in China. Recent studies have explored the correlation between media use and health-promoting behavior by examining the motivation of individuals and the credibility of influencers. However, the role of media affordance has thus far been largely overlooked. Drawing on the theory of Stimulus-Organism- Response (SOR), the study investigated the indirect effect of visibility affordance on the intention to exercise with fitness influencers in the context of cloud fitness through psychological variables. Methods: This paper, based on the online survey data (N = 456), analyses the effect of visibility affordance on the intention to fitness following with influencers. A moderated parallel mediation model was constructed to examine the relationship among related variables. Results: The paper draws the following conclusions: (1) Visibility affordance is positively related to the intention to exercise with fitness influencers. (2) Both the sense of social presence and immersion positively mediate the relationship between visibility affordance and the intention to exercise with fitness influencers. (3) The perceived popularity of the influencer positively moderates the relationship between social presence and the intention to exercise with fitness influencers and moderates the mediating role of social presence. Discussion: Consequently, this study enhances the existing body of knowledge in exercise behavior and health communication literature, and provides practical implications for short video platform, influencers and individuals in promoting healthier behaviors. [ABSTRACT FROM AUTHOR]

The rapid development of substations has increased the demand for accurate and fast fault prediction systems. In order to achieve rapid localization and autonomous decision-making of fault modules and types in substations, the article proposes a fault autonomous localization algorithm based on improved ant colony optimization (IACO) and back propagation neural network (BPNN). The fault data of the substation secondary equipment for training and testing the BPNN model is based on the actual operating equipment of the substation, which can significantly improve the reliability of the model results. In addition, the IACO is used to globally optimize the weights and thresholds of BPNN, and the number of hidden layer nodes in BPNN was analyzed to further improve the accuracy of the established fault prediction algorithm. The test results show that the fault prediction accuracy of the BPNN model optimized by IACO is 93.67%, which is significantly improved compared to the traditional BPNN and BPNN with ant colony optimization method (with an accuracy of 82.98% and 91.04%). The above results effectively demonstrate the high accuracy and effectiveness of the established prediction algorithm in processing data and locating faults, which can improve the maintenance and operational efficiency of substations. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance: Gualou Xiebai Banxia (GLXBBX) decoction is a well-known traditional Chinese herbal formula that was first discussed in the Synopsis of the Golden Chamber by Zhang Zhongjing in the Eastern Han Dynasty. In traditional Chinese medicine, GLXBBX is commonly prescribed to treat cardiovascular diseases, such as coronary heart disease and atherosclerosis. Objective: The present study aimed to examine GLXBBX's preventative capacity and elucidate the potential molecular mechanism of Poloxamer 407 (P407)-induced hyperlipidemia in rats. Materials and methods: Both the control and model groups received pure water, and the test group also received a GLXBBX decoction. For each administration, 3 ml of the solution was administered orally. To establish hyperlipidemia, a solution mixed with 0.25 g/kg P407 dissolved in 0.9% normal saline was injected slowly into the abdominal cavity. At the end of the study, the rats' plasma lipid levels were calculated using an automatic biochemical analyzer to evaluate the preventative capability of the GLXBBX decoction, and the serum and liver of the rats were collected. Results: The GLXBBX decoction significantly improved P407-induced hyperlipidemia, including increased plasma triglycerides (TGs), aspartate aminotransferase (AST) elevation, and lipid accumulation. Moreover, GLXBBX decoction treatment increased lipoprotein lipase (LPL) activity and mRNA expression of LPL. Furthermore, GLXBBX significantly suppressed the mRNA expression of stearoyl-CoA desaturase (SCD1). Conclusion: GLXBBX significantly improved P407-induced hyperlipidemia, which may have been related to enhanced LPL activity, increased LPL mRNA expression, and decreased mRNA expression of SCD1. [ABSTRACT FROM AUTHOR]

The brassinosteroid-SIGNALING KINASE (BSK) belongs to the receptor-like cytoplasmic kinase XII subgroup. BSK1 regulates development and immunity in Arabidopsis. However, the function of rice (Oryza sativa) BSK1 is largely unknown. Here, we report that the expression level of OsBSK1-2 is induced after a chitin or fagellin22 (flg22) treatment. Silencing OsBSK1-2 in rice results in compromised responses to chitin- or flg22-triggered immunity and resistance to Magnaporthe oryzae, but does not alter the plant's architecture nor reduce plant responses to brassinosteroid signaling. Our study reveals that OsBSK1-2 functions as a major regulator in rice plant immunity. [ABSTRACT FROM AUTHOR]

The brassinosteroid-SIGNALING KINASE (BSK) belongs to the receptor-like cytoplasmic kinase XII subgroup. BSK1 regulates development and immunity in Arabidopsis. However, the function of rice (Oryza sativa) BSK1 is largely unknown. Here, we report that the expression level of OsBSK1-2 is induced after a chitin or fagellin22 (flg22) treatment. Silencing OsBSK1-2 in rice results in compromised responses to chitin- or flg22-triggered immunity and resistance to Magnaporthe oryzae, but does not alter the plant’s architecture nor reduce plant responses to brassinosteroid signaling. Our study reveals that OsBSK1-2 functions as a major regulator in rice plant immunity. [ABSTRACT FROM AUTHOR]

This project investigated requestive patterns in elicited vs. spontaneously produced emails sent by students to faculty. We collected 52 emails by 12 Chinese graduate students majoring in Engineering at a university in the southwestern United States and classified them by topic into five categories (Appointment, Committee, Registration, Updates, and Signature). These 12 participants also took a written DCT whose design was based on spontaneously produced emails, and therefore meant to elicit the same kind of requests. We compared the spontaneously produced emails and the elicited texts in term of length, supportive moves, and request perspectives. Descriptive analysis, T test, and Chi square test were performed to investigate the differences. The results showed that participants generated statistically significant longer requests in the spontaneously produced emails than in the written DCT emails, while using similar patterns of supportive moves. The usages of request perspectives were also observed as significantly different in certain situations. [ABSTRACT FROM AUTHOR]

Background: Rice blast disease is one of the most destructive diseases of rice worldwide. We previously cloned the rice blast resistance gene Pid2, which encodes a transmembrane receptor-like kinase containing an extracellular B-lectin domain and an intracellular serine/threonine kinase domain. However, little is known about Pid2-mediated signaling. Results: Here we report the functional characterization of the U-box/ARM repeat protein OsPUB15 as one of the PID2-binding proteins. We found that OsPUB15 physically interacted with the kinase domain of PID2 (PID2K) in vitro and in vivo and the ARM repeat domain of OsPUB15 was essential for the interaction. In vitro biochemical assays indicated that PID2K possessed kinase activity and was able to phosphorylate OsPUB15. We also found that the phosphorylated form of OsPUB15 possessed E3 ligase activity. Expression pattern analyses revealed that OsPUB15 was constitutively expressed and its encoded protein OsPUB15 was localized in cytosol. Transgenic rice plants over-expressing OsPUB15 at early stage displayed cell death lesions spontaneously in association with a constitutive activation of plant basal defense responses, including excessive accumulation of hydrogen peroxide, up-regulated expression of pathogenesis-related genes and enhanced resistance to blast strains. We also observed that, along with plant growth, the cell death lesions kept spreading over the whole seedlings quickly resulting in a seedling lethal phenotype. Conclusions: These results reveal that the E3 ligase OsPUB15 interacts directly with the receptor-like kinase PID2 and regulates plant cell death and blast disease resistance. [ABSTRACT FROM AUTHOR]

Background The nonexpressor of pathogenesis-related genes 1, NPR1 (also known as NIM1 and SAI1), is a key regulator of SA-mediated systemic acquired resistance (SAR) in Arabidopsis. In rice, the NPR1 homolog 1 (NH1) interacts with TGA transcriptional regulators and the Negative Regulator of Resistance (NRR) protein to modulate the SAR response. Though five NPR1 homologs (NHs) have been identified in rice, only NH1 and NH3 enhance immunity when overexpressed. To understand why NH1 and NH3, but not NH2, NH4, or NH5, contribute to the rice immune response, we screened TGA transcription factors and NRR-like proteins for interactions specific to NH1 and NH3. We also examined their co-expression patterns using publicly available microarray data. Results We tested five NHs, four NRR homologs (RHs), and 13 rice TGA proteins for pair-wise protein interactions using yeast two-hybrid (Y2H) and split YFP assays. A survey of 331 inter-family interactions revealed a broad, complex protein interaction network. To investigate preferred interaction partners when all three families of proteins were present, we performed a bridged split YFP assay employing YFPN-fused TGA, YFPC-fused RH, and NH proteins without YFP fusions. We found 64 tertiary interactions mediated by NH family members among the 120 sets we examined. In the yeast two-hybrid assay, each NH protein was capable of interacting with most TGA and RH proteins. In the split YFP assay, NH1 was the most prevalent interactor of TGA and RH proteins, NH3 ranked the second, and NH4 ranked the third. Based on their interaction with TGA proteins, NH proteins can be divided into two subfamilies: NH1, NH2, and NH3 in one family and NH4 and NH5 in the other. In addition to evidence of overlap in interaction partners, co-expression analyses of microarray data suggest a correlation between NH1 and NH3 expression patterns, supporting their common role in rice immunity. However, NH3 is very tightly co-expressed with RH1 and RH2, while NH1 is strongly, inversely co-expressed with RH proteins, representing a difference between NH1 and NH3 expression patterns. Conclusions Our genome-wide surveys reveal that each rice NH protein can partner with many rice TGA and RH proteins and that each NH protein prefers specific interaction partners. NH1 and NH3 are capable of interacting strongly with most rice TGA and RH proteins, whereas NH2, NH4, and NH5 have weaker, limited interaction with TGA and RH proteins in rice cells. We have identified rTGA2.1, rTGA2.2, rTGA2.3, rLG2, TGAL2 and TGAL4 proteins as the preferred partners of NH1 and NH3, but not NH2, NH4, or NH5. These TGA proteins may play an important role in NH1- and NH3-mediated immune responses. In contrast, NH4 and NH5 preferentially interact with TGAL5, TGAL7, TGAL8 and TGAL9, which are predicted to be involved in plant development. [ABSTRACT FROM AUTHOR]

This study developed an improved Eulerian model for the simulation of an air-water flow field over stepped spillways. The improved drag model applied different drag coefficients for bubbles and for free surface flows or gas cavities. Void fraction and turbulence correction were used in determining the bubble drag coefficient. The calculated air entrainment and air-water velocity could be adapted using these parameters. With the improved drag model, the Eulerian simulations predicted the location of the inception point, the distributions of air void fraction, velocity distributions, and pressure distributions. The change in the dissolved oxygen (DO) concentration from upstream of the stepped spillways, to downstream, was simulated based on the improved computational fluid dynamics model and the transport equation for DO transferring. The numerical DO concentra-tion coincided with the experimental results. Therefore, the improved CFD model and the numerical methods presented here can provide possible optimization tools for strong air entrainment flows. [ABSTRACT FROM AUTHOR]

Mixed-linkage glucan (MLG) is a cell wall polysaccharide containing a backbone of unbranched (1,3)- and (1,4)-linked β-glucosyl residues. Based on its occurrence in plants and chemical characteristics, MLG has primarily been associated with the regulation of cell wall expansion due to its high and transient accumulation in young, expanding tissues. The Cellulose synthase-like F (CslF) subfamily of glycosyltransferases has previously been implicated in mediating the biosynthesis of this polymer. We confirmed that the rice (Oryza sativa) CslF6 gene mediates the biosynthesis of MLG by overexpressing it in Nicotiana benthamiana. Rice cslf6 knockout mutants show a slight decrease in height and stem diameter but otherwise grew normally during vegetative development. However, cslf6 mutants display a drastic decrease in MLG content (97% reduction in coleoptiles and virtually undetectable in other tissues), Immunodetection with an anti-MLG monoclonal antibody revealed that the coleoptiles and leaves retain trace amounts of MLG only in specific cell types such as sclerenchyma fibers. These results correlate with the absence of endogenous MLG synthase activity in mutant seedlings and 4-week-old sheaths. Mutant cell walls are weaker in mature stems but not seedlings, and more brittle in both stems and seedlings, compared to wild type. Mutants also display lesion mimic phenotypes in leaves, which correlates with enhanced defense-related gene expression and enhanced disease resistance. Taken together, our results underline a weaker role of MLG in cell expansion than previously thought, and highlight a structural role for MLG in nonexpanding, mature stem tissues in rice. [ABSTRACT FROM AUTHOR]

In the early 1970s, the Xa21 gene from the wild rice species Oryza longistaminata drew attention of rice breeders because of its broad-spectrum resistance to diverse strains of a serious bacterial disease of rice in Asia and Africa, called ‘bacterial blight disease’, caused by the Gram-negative bacterium, Xanthomonas oryzae pv. oryzae ( Xoo). In 1995, we isolated the gene controlling this resistance and in 2009 demonstrated that XA21 recognizes a highly conserved peptide, called ‘Ax21’ (activator of XA21-mediated immunity). Tyrosine sulfation of Ax21 is required for recognition by rice XA21. A decade of genetic, molecular and biochemical studies have uncovered key components of the XA21-mediated signalling cascade. Ax21 recognition by XA21 at the cell surface induces phosphorylation-mediated events, which are predicted to alter subcellular localization and/or DNA-binding activity of a WRKY family of transcription factors. Because XA21 is representative of the large number of predicted pattern recognition receptors (PRRs) in rice ( n = 328), Arabidopsis ( n = 35) and other plant species, further characterization of XA21-mediated signalling pathways will contribute to elucidation of these important defence responses. [ABSTRACT FROM AUTHOR]

Cell-surface pattern recognition receptors (PRRs) are key components of the innate immune response in animals and plants. These receptors typically carry or associate with non-RD kinases to control early events of innate immunity signaling. Despite their importance, the mode of regulation of PRRs is largely unknown. Here we show that the rice PRR, XA21, interacts with XA21 binding protein 24 (XB24), a previously undescribed ATPase. XB24 promotes autophosphorylation of XA21 through its ATPase activity. Rice lines silenced for Xb24 display enhanced XA21-mediated immunity, whereas rice lines overexpressing XB24 are compromised for immunity. XB24 ATPase enzyme activity is required for XB24 function. XA21 is degraded in the presence of the pathogen-associated molecular pattern Ax21 when XB24 is overexpressed. These results demon- strate a function for this large class of broadly conserved ATPases in PRR-mediated immunity. [ABSTRACT FROM AUTHOR]

The rice protein phosphatase 2C XB15 is a negative regulator of pathogen recognition receptor kinase-mediated cell death and innate immunity. [ABSTRACT FROM AUTHOR]

The rice Xa21 gene, which confers resistance to the bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo), encodes a receptor-like kinase. Few components involved in transducing the Xa21-mediated defense response have yet been identified. Here, we report that XA21 binds to a WRKY transcription factor, called OsWRKY62. The OsWRKY62 gene encodes two splice variants (OsWRKY62.1 and OsWRKY62.2). OsWRKY62.1:smGFP2 and OsWRKY62.2:smGFP2 fusion proteins partially localize to the nucleus. Transgenic plants overexpressing OsWRKY62.1 are compromised in basal defense and Xa21-mediated resistance to Xoo. Furthermore, overexpression of OsWRKY62.1 suppresses the activation of defense-related genes. These results imply that OsWRKY62 functions as a negative regulator of innate immunity in rice, and serves as a critical mediator of both basal and race-specific defense responses. [ABSTRACT FROM PUBLISHER]

Rice blast, caused by the fungal pathogen Magnaporthe grisea, is one of the most devastating diseases in rice worldwide. The dominant resistance gene, Pi-d2 [previously named Pi-d(t)2], present in the rice variety Digu, confers gene-for-gene resistance to the Chinese blast strain, ZB15. Pi-d2 was previously mapped close to the centromere of chromosome 6. In this study, the Pi-d2 gene was isolated by a map-based cloning strategy. Pi-d2 encodes a receptor-like kinase protein with a predicted extracellular domain of a bulb-type mannose specific binding lectin (B-lectin) and an intracellular serine–threonine kinase domain. Pi-d2 is a single-copy gene that is constitutively expressed in the rice variety Digu. Transgenic plants carrying the Pi-d2 transgene confer race-specific resistance to the M. grisea strain, ZB15. The Pi-d2 protein is plasma membrane localized. A single amino acid difference at position 441 of Pi-d2 distinguishes resistant and susceptible alleles of rice blast resistance gene Pi-d2. Because of its novel extracellular domain, Pi-d2 represents a new class of plant resistance genes. [ABSTRACT FROM AUTHOR]

We combined cDNA amplified fragment length polymorphism (cDNA-AFLP) with bulked segregant analysis (BSA) to detect genes that control rice blast (Magnaporthe grisea) resistance in a double-haploid (DH) population derived from a cross between a blast-resistant variety, Zhai Ye Qing8 (ZYQ8), and a blast-susceptible variety, Jin Xi17 (JX17). In cDNA-AFLP analysis between a blast resistance (R) pool and a blast susceptibility (S) pool from the DH population, 12 transcript-derived fragments (TDFs) that were present in only one of the two pools were detected, 8 of which were from the R pool and 4 from the S pool. Mapping analysis of these TDFs by using the DH mapping population showed that five of them, R1, R8, S9, S16 and S17, were located on chromosome 1. Sequence comparison and allelic analysis showed thatR1/S16 and R8/S9 were two pairs of allelic genes. The full-length cDNA sequences of R1/S16, S17 and R8/S were obtained through cDNA library screening, in which only the expression level of R8 cDNA was up-regulated by inoculation with the blast isolate zh10814 and not affected by mock treatment, suggesting that R8 was implicated in the signaling pathways of the rice blast resistance reaction. Protein function prediction showed that R8 cDNA encodes a protein with high identity to a putative calmodulin-binding protein in Arabidopsis thaliana which belongs to the P-loop-containing nucleotide triphosphate hydrolases superfamily that contains a number of various kinases. [ABSTRACT FROM AUTHOR]

We combined cDNA amplified fragment length polymorphism (cDNA-AFLP) with bulked segregant analysis (BSA) to detect genes that control rice blast (Magnaporthe grisea) resistance in a double-haploid (DH) population derived from a cross between a blast-resistant variety, Zhai Ye Qing8 (ZYQ8), and a blast-susceptible variety, Jin Xi17 (JX17). In cDNA-AFLP analysis between a blast resistance (R) pool and a blast susceptibility (S) pool from the DH population, 12 transcript-derived fragments (TDFs) that were present in only one of the two pools were detected, 8 of which were from the R pool and 4 from the S pool. Mapping analysis of these TDFs by using the DH mapping population showed that five of them, R1, R8, S9, S16 and S17, were located on chromosome 1. Sequence comparison and allelic analysis showed thatR1/S16 and R8/S9 were two pairs of allelic genes. The full-length cDNA sequences of R1/S16, S17 and R8/S were obtained through cDNA library screening, in which only the expression level of R8 cDNA was up-regulated by inoculation with the blast isolate zh10814 and not affected by mock treatment, suggesting that R8 was implicated in the signaling pathways of the rice blast resistance reaction. Protein function prediction showed that R8 cDNA encodes a protein with high identity to a putative calmodulin-binding protein in Arabidopsis thaliana which belongs to the P-loop-containing nucleotide triphosphate hydrolases superfamily that contains a number of various kinases. [ABSTRACT FROM AUTHOR]

Presents a study which conducted a molecular tagging of the Pingxiang dominant genic male-sterile rice from China. Methodology; Results; Discussion.

Focuses on a study which examined the fine mapping of the rice bacterial blight resistance gene using an F[sub 2] population derived from the Xa-4 near isogenic lines, IR24 and IRBB4. Materials and methods; Presentation of results; Discussion of findings.

A correction to the article "Rice XB15, a Protein Phosphatase 2C, Negatively Regulates Cell Death and XA21-Mediated Innate Immunity," that was published in the November 25, 2008 issue is presented.