A systems biology approach identifies a regulator, BplERF1, of cold tolerance in Betula platyphylla

Cold is an abiotic stress that can greatly affect the growth and survival of plants. Here, we reported that an AP2/ERF family gene, BplERF1, isolated from Betula platyphylla played a contributing role in cold stress tolerance. Overexpression of BplERF1 in B. platyphylla transgenic lines enhanced cold stress tolerance by increasing the scavenging capability and reducing H2O2 and malondialdehyde (MDA) content in transgenic plants. Construction of BplERF-mediated multilayered hierarchical gene regulatory network (ML-hGRN), using Top-down GGM algorithm and the transcriptomic data of BplERF1 overexpression lines, led to the identification of five candidate target genes of BplERF1 which include MPK20, ERF9, WRKY53, WRKY70, and GIA1. All of them were then verified to be the true target genes of BplERF1 by chromatin-immunoprecipitation PCR (ChIP-PCR) assay. Our results indicate that BplERF1 is a positive regulator of cold tolerance and is capable of exerting regulation on the expression of cold signaling and regulatory genes, causing mitigation of reactive oxygen species

Studies on the toxicokinetics of intragastricallyadministered paracetamol, aminophenazone, caffeine and chlorphenamine maleate tablets in rats

Purpose: To study the toxicokinetics of paracetamol (PCT), aminophenazone (ACP), caffeine (CFN) and chlorphenamine maleate (CPM) tablets after a single oral gavage, and after oral gavage for 14 consecutive days in rats. Methods: Eighty Sprague Dawley (SD) rats (half male, half female) were randomly divided into 4 groups with 20 rats in each group. Half of the rats were used for the toxicokinetic test after a single oral gavage of PCT, ACP, CFN and CPM tablets, while rats in the other half were used for the toxicokinetic tests after oral gavage for 14 consecutive days. The doses of the four groups were set as 0, 0.5, 1 and 2 tablets/kg body weight, respectively. Blood was taken from the rats and the plasma concentration of paracetamol was determined. Results: There was a significant difference in AUC0-∞ between male and female rats at single oral gavage of 2 tablets/kg of each of the drugs. The exposure amount of PCT (AUC0~t, AUC0-∞ and Cmax) increased with increase in dose, and showed a good linear relationship after a single intragastric administration of each drug, and after 14 consecutive days of intragastric administration at low, medium and high doses. Conclusion: The amount of PCT to which SD rats are exposed after a single intragastric administration of PCT, ACP, CFN and CPM tablets is lower in male than in female rats. However, no significant gender difference in exposure results when these drugs are given intragastrically for 14 consecutive days

An efficient magnetic carbon-based solid acid treatment for corncob saccharification with high selectivity of xylose and enhanced enzymatic digestibility

An effective method for corncob saccharification was investigated over a magnetic carbon-based solid acid (MMCSA) catalyst in the aqueous phase. MMCSA was synthesized through a simple and inexpensive impregnation-carbonization-sulfonation process. Under the optimal reaction conditions (150 °C, 2 h, 0.5 g corncob, 0.5 g catalyst and 50 ml deionized water), 74.9% of xylose yield was directly obtained from corncob, with 91.7% cellulose retention in the residue. After reaction, the MMCSA was easily separated from the residue by an external magnet and reused 4 times showing high stability and catalytic activity. The enzymatic digestibility of the pretreated residue reached 95.2%, with a total sugar yield of 90.4%. The morphologic and structural properties of the natural and treated corncobs were analyzed primarily through 3D X-ray microscopy to characterize the cell wall thickness, porosity, and pore surface area distribution. The increase of macropores (pore surface areas > 200 μm2) was beneficial to the accessibility of cellulose to cellulosic enzymes, so the enzymatic digestibility was enhanced immediately. Compared with other traditional hydrolysis methods, this two-step hydrolysis approach represents an environmentally friendly and sustainable saccharification of lignocellulose to produce xylose and glucose while achieving the same level of reaction efficiency

Cytoplasm affects grain weight and filled-grain ratio in indica rice

<p>Abstract</p> <p>Background</p> <p>Cytoplasmic effects on agronomic traits -involving cytoplasmic and nuclear genomes of either different species or different cultivars - are well documented in wheat but have seldom been demonstrated in rice (<it>Oryza sativa </it>L.). To detect cytoplasmic effects, we introgressed the nuclear genomes of three <it>indica </it>cultivars - Guichao 2, Jiangchengkugu, and Dianrui 449 - into the cytoplasms of six <it>indica </it>cultivars - Dijiaowujian, Shenglixian, Zhuzhan, Nantehao, Aizizhan, and Peta. These 18 nuclear substitution lines were evaluated during the winter season of 2005 in Sanya, Hainan, China, and during the summer season of 2006 in Kunming, Yunnan, China. The effects of 6 cytoplasm sources, 3 nucleus sources, 2 locations and their interactions were estimated for plant height, panicle length, panicle number per plant, spikelet number per panicle, grain weight, filled-grain ratio, and yield per plot.</p> <p>Results</p> <p>For five of the seven traits, analysis of variance showed that there were no significant cytoplasmic effects or interactions involving cytoplasmic effects. The effect of cytoplasm on 1000-grain weight was highly significant. Mean 1000-grain weight over the two locations in four of the six cytoplasms clustered close to the overall mean, whereas plants with Nantehao cytoplasm had a high, and those with Peta cytoplasm a low mean grain weight. There was a highly significant three-way interaction affecting filled-grain ratio. At Sanya, cytoplasms varied in very narrow ranges within nuclear backgrounds. Strong cytoplasmic effects were observed only at Kunming and in only two of the three nuclear backgrounds; in the Jianchenkugu nuclear background, there was no evidence of strong cytoplasmic effects at either location. In the Dianrui 449 and Guichao 2 nuclear background evaluated at Kunming, filled-grain ratios of the six cytoplasms showed striking rank shifts</p> <p>Conclusions</p> <p>We detected cytoplasmic variation for two agronomically important traits in <it>indica </it>rice. The cytoplasm source had a significant effect on grain weight across the two experimental locations. There was also a significant cytoplasmic effect on filled-grain ratio, but only in two of three nuclear background and at one of the two locations. The results extend our previous findings with <it>japonica </it>rice, suggesting that the selection of appropriate cytoplasmic germplasm is broadly important in rice breeding, and that cytoplasmic effects on some traits, such as filled-grain ratio, cannot be generalized; effects should be evaluated in the nuclear backgrounds of interest and at multiple locations.</p

A Systematic RNAi Screen Reveals a Novel Role of a Spindle Assembly Checkpoint Protein BuGZ in Synaptic Transmission in C. elegans

Synaptic vesicles (SV) store various neurotransmitters that are released at the synapse. The molecular mechanisms of biogenesis, exocytosis, and endocytosis for SV, however, remain largely elusive. In this study, using Complex Object Parametric Analysis and Sorter (COPAS) to monitor the fluorescence of synapto-pHluorin (SpH), we performed a whole-genome RNAi screen in C. elegans to identify novel genetic modulators in SV cycling. One hundred seventy six genes that up-regulating SpH fluorescence and 96 genes that down-regulating SpH fluorescence were identified after multi-round screen. Among these genes, B0035.1 (bugz-1) encodes ortholog of mammalian C2H2 zinc-finger protein BuGZ/ZNF207, which is a spindle assembly checkpoint protein essential for mitosis in human cells. Combining electrophysiology, imaging and behavioral assays, we reveal that depletion of BuGZ-1 results in defects in locomotion. We further demonstrate that BuGZ-1 promotes SV recycling by regulating the expression levels of endocytosis-related genes such as rab11.1. Therefore, we have identified a bunch of potential genetic modulators in SV cycling, and revealed an unexpected role of BuGZ-1 in regulating synaptic transmission

MECHANICAL ANALYSIS OF HIGH-SPEED RAILWAY SLAB BALLASTLESS TRACK UNDER WORKING CONDITION

In order to study the mechanical properties of the ballastless track structure under the load of the train, this paper simplified the ballastless track structure to an infinite double-layer elastic beam. The double-layer elastic beam model and its theoretical expression formula was established using the elastic foundation beam concept. When the train was at a certain position on the rail, the differential balance equation between the rail and the concrete slab was established under the action of the vehicle load. Combined with the generalized “initial parameter method” and its boundary conditions, the analytical solution of the double-layer beam displacement and stress were obtained under the vehicle load. Through calculation examples, the displacement and stress of the rail and concrete slab were analyzed, and the analytical results were compared with the results of ANSYS, which proved the reliability of the analytical solution. Therefore, simplifying the slab ballastless track into infinite double-layer elastic beam is closer to the actual working conditions. The results can provide a reliable basis for the theoretical study of the ballastless track of high-speed railways and design reference for related projects

A R2R3-MYB Transcription Factor Gene, BpMYB123, Regulates BpLEA14 to Improve Drought Tolerance in Betula platyphylla

Drought stress causes various negative impacts on plant growth and crop production. R2R3-MYB transcription factors (TFs) play crucial roles in the response to abiotic stress. However, their functions in Betula platyphylla haven’t been fully investigated. In this study, a R2R3 MYB transcription factor gene, BpMYB123, was identified from Betula platyphylla and reveals its significant role in drought stress. Overexpression of BpMYB123 enhances tolerance to drought stress in contrast to repression of BpMYB123 by RNA interference (RNAi) in transgenic experiment. The overexpression lines increased peroxidase (POD) and superoxide dismatase (SOD) activities, while decreased hydrogen peroxide (H2O2), superoxide radicals (O2–), electrolyte leakage (EL) and malondialdehyde (MDA) contents. Our study showed that overexpression of BpMYB123 increased BpLEA14 gene expression up to 20-fold due to BpMYB123 directly binding to the MYB1AT element of BpLEA14 promoter. These results indicate that BpMYB123 acts as a regulator via regulating BpLEA14 to improve drought tolerance in birch