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Jinshan Zhang Zhenyu Zhou Jinjuan Bai Xiaoping Tao Ling Wang Hui Zhang Jian-Kang Zhu 《国家科学评论(英文版)》2020,7(1):102
The microRNA miR396 directly represses GROWTH-REGULATING FACTORs (OsGRFs) and has been implicated in regulating rice yield and in nitrogen assimilation. Overexpressing the miR396 targets OsGRF4 and OsGRF6 improves rice yield via increased grain size and panicle branching, respectively. Here, we used CRISPR/Cas9 to assess the function of miR396 genes in rice. Knockout of MIR396ef (MIR396e and MIR396f), but not other isoforms, enhanced both grain size and panicle branching, resulting in increased grain yield. Importantly, under nitrogen-deficient conditions, mir396ef mutants showed an even higher relative increase in grain yield as well as elevated above-ground biomass. Furthermore, we identified OsGRF8 as a new target of miR396, in addition to the known targets OsGRF4 and OsGRF6. Disruption of the miR396-targeting site in OsGRF8 was sufficient to both enlarge grain size and elongate panicles. Our results suggest that rice-seed and panicle development are regulated by miR396ef-GRF4/6/8-GIF1/2/3 modules and that miR396ef are promising targets of genome editing for breeding environmentally friendly rice varieties that require less nitrogen fertilization. 相似文献
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BackgroundProfilin proteins (PRFs) are small (12–15 kD) actin-binding protein, which play a significant role in cytoskeleton dynamics and plant development via regulating actin polymerization. Profilins have been well documented in Arabidopsis, Zea mays L. as well as Phaseolus vulgaris, however no such fully characterization of rice (Oryza sativa L.) profilin gene family has been reported thus far.ResultIn the present study, a comprehensive genome-wide analysis of rice PRF genes was completed and three members were identified. OsPRF1 and OsPRF2 shared 98.5% similarity (6 nucleotide divergence), but the deduced amino acid sequences of OsPRF1 and OsPRF2 are fully identical. In contrast, the OsPRF3 presents relatively lower similarity with OsPRF1 and OsPRF2. Phylogenetic analysis also support that OsPRF1 has a closer relationship with OsPRF2. Expression pattern analysis revealed the differential expression of OsPRFs in tissues of mature plant, which suggested the potential spatial functional specificity for rice profilin genes. Subcellular localization analysis revealed the OsPRFs were localized in cytoplasm and nucleus and all of them could bind actin monomers. Furthermore, abiotic stresses and hormones treatments assay indicated that the three OsPRF genes could be differentially regulated, suggesting that OsPRF genes might participate in different stress processes in rice.ConclusionsTaken together, our study provides a comprehensive analysis of the OsPRF gene family and will provide a basis for further studies on their roles in rice development and in response to abiotic stresses.How to cite: Zhang Y, Dong G, Wu L, et al. Identification and characterization of profilin gene family in rice. Electron J Biotechnol 2021;54. https://doi.org/10.1016/j.ejbt.2021.08.004. 相似文献
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本文运用半试验与调查相结合的方法,以贵州省从江县传统农业地区的糯稻和杂交稻为例,研究了传统品种和现代品种在水稻单作(R)、稻-鱼(R-F)和稻-鱼-鸭(R-F-D)3种不同稻作方式下,稻田多个物种共存对稻田生态系统主要病虫草害及蜘蛛的影响。结果表明,就水稻品种而言,糯稻在3种稻作方式下的抑制杂草能力均优于杂交稻,糯稻田与杂交稻田的稻飞虱虫量、稻纵卷叶螟虫量以及蜘蛛量差异不显著,杂交稻在3种稻作方式下的抗稻瘟病能力显著高于糯稻。就稻作方式而言,R-F-D显著降低了田间杂草的发生密度,对稻田杂草鸭舌草(Monochoria vaginalis)、节节菜(Rotala indica)等的抑制效果达到100%,总体抑制效果显著优于其它的稻作方式;R-F-D系统的稻飞虱、稻纵卷叶螟虫量较水稻单作明显减少;R-F系统的蜘蛛数量最高;R-F-D系统的抗稻瘟病性最好。 相似文献
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BackgroundEthylene plays an important role in the regulation of floral organ development in soybean, and 1-aminocyclopropane-1-carboxylate synthase (ACS) is a rate-limiting enzyme for ethylene biosynthesis. However, whether ACS also regulates floral organ differentiation in soybean remains unknown. To address this, we constructed an RNAi vector to inhibit ACS expression in cotyledonary nodes. Linear DNA cassettes of RNAi-ACS obtained by PCR were used to transform soybean cotyledonary nodes.ResultsIn total, 131 of 139 transiently transformed plants acquired herbicide resistance and displayed GUS activities in the new buds. In comparison to untransformed seedling controls, a greater number of flower buds were differentiated at the cotyledonary node; GM-ACS1 mRNA expression levels and ethylene emission in the transformed buds were reduced.ConclusionThese results indicate that the cotyledonary node transient transformation system may be suitable for stable transformation and that the inhibition of ACS expression may be an effective strategy for promoting floral organ differentiation in soybean. 相似文献
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This paper addresses the positive filter design problem for a class of continuous-discrete Roesser model in Takagi-Sugeno fuzzy form. Both the observer-based and the general form of filters are designed with l1 performance constraint. By utilizing the co-positive Lyapunov function approach, sufficient criteria are derived in the form of linear programming, which not only guarantee the existence of the positive lower-bounding/upper-bounding filters but also assure the resulting filtering error system to be asymptotically stable and having a prescribed l1-gain performance index. In addition, the explicit design schemes for the corresponding filter parameters are also presented. Finally, two numerical examples are provided to illustrate effectiveness of the proposed results. 相似文献
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BackgroundPiercing/sucking insect pests in the order Hemiptera causes substantial crop losses by removing photoassimilates and transmitting viruses to their host plants. Cloning and heterologous expression of plant-derived insect resistance genes is a promising approach to control aphids and other sap-sucking insect pests. While expression from the constitutive 35S promoter provides broad protection, the phloem-specific rolC promoter provides better defense against sap sucking insects. The selection of plant-derived insect resistance genes for expression in crop species will minimize bio-safety concerns.ResultsPinellia ternata leaf agglutinin gene (pta), encodes an insecticidal lectin, was isolated and cloned under the 35S and rolC promoters in the pGA482 plant transformation vector for Agrobacterium-mediated tobacco transformation. Integration and expression of the transgene was validated by Southern blotting and qRT-PCR, respectively. Insect bioassays data of transgenic tobacco plants showed that expression of pta under rolC promoter caused 100% aphid mortality and reduced aphid fecundity up to 70% in transgenic tobacco line LRP-9. These results highlight the better effectivity of pta under rolC promoter to control phloem feeders, aphids.ConclusionsThese findings suggested the potential of PTA against aphids and other sap sucking insect pests. Evaluation of gene in tobacco under two different promoters; 35S constitutive promoter and rolC phloem-specific promoter could be successfully use for other crop plants particularly in cotton. Development of transgenic cotton plants using plant-derived insecticidal, PTA, would be key step towards commercialization of environmentally safe insect-resistant crops.How to citeUmer N, Naqvi RZ, Rauf I, et al. Expression of Pinellia ternata leaf agglutinin under rolC promoter confers resistance against a phytophagous sap sucking aphid, Myzus persicae. Electron J Biotechnol 2020;47. https://doi.org/10.1016/j.ejbt.2020.07.004. 相似文献
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BackgroundRice sheath blight (caused by Rhizoctonia solani) and tobacco mosaic virus are very important plant diseases, causing a huge loss in global crop production. Paenibacillus kribbensis PS04 is a broad-spectrum biocontrol agent, used for controlling these diseases. Previously, extracellular polysaccharides (EPS) from P. kribbensis PS04 had been purified and their structure was inferred to be fructosan. This study aimed to evaluate the effects of exogenous EPS treatment on plant–pathogen interactions.ResultsPlant defense genes such as phenylalanine ammonia-lyase, catalase, chitinase, allene oxide synthase, and PR1a proteins were significantly induced by exogenous EPS treatment. Moreover, subsequent challenge of EPS-pretreated plants with the pathogens (R. solani or tobacco mosaic virus) resulted in higher expression of defense-associated genes. Increased activities of defense-associated enzymes, total phenols, and flavonoids were also observed in EPS pretreated plants. The contents of malondialdehyde in plants, which act as indicator of lipid peroxidation, were reduced by EPS treatment.ConclusionsThis study comprehensively showed that EPS produced from P. kribbensis PS04 enhances disease resistance in plants by the activation of defense-associated genes as well as through the enhancement of activities of defense-related enzymes.How to citeCanwei S, Xiaoyun H, Ahmed N, et al. Fructosan form Paenibacillus kribbensis PS04 enhance disease resistance against Rhizoctonia solani and tobacco mosaic virus. Electron J Biotechnol 2020;47. https://doi.org/10.1016/j.ejbt.2020.07.002 相似文献
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In many phase-locked loop (PLL) applications, the natural pull-in mechanism is too slow and unreliable, and it must be accelerated. By adding an externally-generated ramp to its control voltage input, the PLL voltage controlled oscillator (VCO) frequency can be swept towards the input reference frequency in an attempt to speed up the pull-in process. This popular acquisition aid has a significant limitation when it is used in a second-order, Type II PLL. If the applied ramp voltage has a slope magnitude greater than (alternatively, less than) some value Rm, the PLL state can (alternatively, cannot) sweep past the desired lock point, resulting in a phase lock failure (alternatively, success). In general, the maximum sweep rate magnitude Rm can be computed by using a numerical integration-and-search procedure that is described in the PLL literature. A special case exists for a second-order, Type II PLL that incorporates a triangular-characteristic phase detector (with logic-level binary input signals). For this case, it is possible to develop an exact, closed-form expression for Rm, the main result of this paper. For a range of loop parameters most often used in applications, Rm values are computed by using the exact formula, and these are used in two ways. First, they are used to validate the previously-mentioned numerical integration-and-search procedure. Second, they are compared to maximum sweep rate values computed for a PLL that utilizes a sinusoidal phase detector to show that the triangular-phase-detector PLL can be swept significantly faster than the sinusoidal-phase-detector loop. 相似文献
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BackgroundThe bioethanol produced from biomass is a promising alternative fuel. The lignocellulose from marginal areas or wasteland could be a promising raw material for bioethanol production because it is present in large quantities, is cheap, renewable and has favorable environmental properties. Despite these advantages, lignocellulosic biomass is much more difficult to process than cereal grains, due to the need for intensive pretreatment and relatively large amounts of cellulases for efficient hydrolysis. Therefore, there is a need to develop an efficient and cost-effective method for the degradation and fermentation of lignocellulosic biomass to ethanol.ResultsThe usefulness of lignocellulosic biomass from wasteland for the production of bioethanol using pretreatment with the aid of ionic liquids of 1-ethyl-3-methylimidazolium acetate and 1-ethyl-3-methylimidazolium chloride was evaluated in this study. The pretreatment process, enzymatic hydrolysis and alcoholic fermentation lasted a total of 10 d. The largest amounts of bioethanol were obtained from biomass originating from agricultural wasteland, in which the dominant plant was fireweed (Chamaenerion angustifolium) and from the field where the common broom (Cytisus scoparius) was the dominant.ConclusionsThe plants such as fireweed, common broom, hay and goldenrod may be useful for the production of liquid biofuels and it would be necessary in the further stage of research to establish and optimize the conditions for the technology of ethyl alcohol producing from these plant species. Enzymatic hydrolysis of biomass from agricultural wastelands results in a large increase in fermentable sugars, comparable to the enzymatic hydrolysis of rye, wheat, rice or maize straw.How to cite: Smuga-Kogut M, Piskier T, Walendzik B, et al. Assessment of wasteland derived biomass for bioethanol production. Electron J Biotechnol 2019;41. https://doi.org/10.1016/j.ejbt.2019.05.001. 相似文献
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《Electronic Journal of Biotechnology》2014,17(2):95-101
BackgroundWeedy rice (Oryza sativa L.) is a noxious form of cultivated rice (O. sativa L.) associated with intensive rice production and dry seeding. A cost-efficient strategy to control this weed is the Clearfield rice production system, which combines imidazolinone herbicides with mutant imidazolinone-resistant rice varieties. However, imidazolinone resistance mutations can be introgressed in weedy rice populations by natural outcrossing, reducing the life span of the Clearfield technology. Timely and accurate detection of imidazolinone resistance mutations in weedy rice may contribute to avoiding the multiplication and dispersion of resistant weeds and to protect the Clearfield system. Thus, highly sensitive and specific methods with high throughput and low cost are needed. KBioscience’s Allele Specific PCR (KASP) is a codominant, competitive allele-specific PCR-based genotyping method. KASP enables both alleles to be detected in a single reaction in a closed-tube format. The aim of this work is to assess the suitability and validity of the KASP method for detection in weedy rice of the three imidazolinone resistance mutations reported to date in rice.ResultsValidation was carried out by determining the analytical performance of the new method and comparing it with conventional allele-specific PCR, when genotyping sets of cultivated and weedy rice samples. The conventional technique had a specificity of 0.97 and a sensibility of 0.95, whereas for the KASP method, both parameters were 1.00.ConclusionsThe new method has equal accuracy while being more informative and saving time and resources compared with conventional methods, which make it suitable for monitoring imidazolinone-resistant weedy rice in Clearfield rice fields. 相似文献
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BackgroundGain-of-function of fibroblast growth factor receptor 3 (FGFR3) is involved in the pathogenesis of many tumors. More and more studies have focused on the potential usage of therapeutic single-chain Fv (ScFv) antibodies against FGFR3. RNA interference (RNAi) has been considered as a promising therapeutic method against cancer. A tool which can deliver small interference RNAs (siRNAs) into FGFR3 positive cancer cells is very promising for anti-tumor therapy.ResultsIn this study, a novel fusion protein R3P, which consists of FGFR3-ScFv and protamine, was generated in Escherichia coli by inclusion body expression strategy and Ni-NTA chromatography. Its yield reached 10 mg per liter of bacterial culture and its purity was shown to be higher than 95%. 1 μg of R3P could efficiently bind to about 2.5 pmol siRNAs and deliver siRNAs into FGFR3 positive RT112 and K562 cells. Annexin V staining results showed that R3P can deliver the amplified breast cancer 1 (AIB1) siRNAs to induce RT112 cell apoptosis.ConclusionThese results indicated that R3P was a promising carrier tool to deliver siRNAs into FGFR3 positive cancer cells and to exert anti-tumor effect. 相似文献
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BackgroundAvailability of related rice species is critical for rice breeding and improvement. Two distinct species of domesticated rice exist in the genus Oryza: Oryza sativa (Asian rice) and Oryza glaberrima (African rice). New rice for Africa (NERICA) is derived from interspecific crosses between these two species. Molecular profiling of these germplasms is important for both genetics and breeding studies. We used 30 polymorphic SSR markers to assess the genetic diversity and molecular fingerprints of 53 rice genotypes of O. sativa, O. glaberrima, and NERICA.ResultsIn total, 180 alleles were detected. Average polymorphism information content and Shannon's information index were 0.638 and 1.390, respectively. Population structure and neighbor-joining phylogenetic tree revealed that 53 genotypes grouped into three distinct subpopulations conforming to the original three groups, except three varieties (IR66417, WAB450-4, MZCD74), and that NERICA showed a smaller genetic distance from O. sativa genotypes (0.774) than from O. glaberrima genotypes (0.889). A molecular fingerprint map of the 53 accessions was constructed with a novel encoding method based on the SSR polymorphic alleles. Ten specific SSR markers displayed different allelic profiles between the O. glaberrima and O. sativa genotypes.ConclusionsGenetic diversity studies revealed that 50 rice types were clustered into different subpopulations whereas three genotypes were admixtures. Molecular fingerprinting and 10 specific markers were obtained to identify the 53 rice genotypes. These results can facilitate the potential utilization of sibling species in rice breeding and molecular classification of O. sativa and O. glaberrima germplasms. 相似文献
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BackgroundBiomineralization is a significant process performed by living organisms in which minerals are produced through the hardening of biological tissues. Herein, we focus on calcium carbonate precipitation, as part of biomineralization, to be used in applications for environmental protection, material technology, and other fields. A strain GM-1, Microbacterium sp. GM-1, isolated from active sludge, was investigated for its ability to produce urease and induce calcium carbonate precipitation in a metabolic process.ResultsIt was discovered that Microbacterium sp. GM-1 resisted high concentrations of urea up to 60 g/L. In order to optimize the calcification process of Microbacterium sp. GM-1, the concentrations of Ni2 + and urea, pH value, and culture time were analyzed through orthogonal tests. The favored calcite precipitation culture conditions were as follows: the concentration of Ni2 + and urea were 50 μM and 60 g/L, respectively, pH of 10, and culture time of 96 h. Using X-ray diffraction analysis, the calcium carbonate polymorphs produced by Microbacterium sp. GM-1 were proven to be mainly calcite.ConclusionsThe results of this research provide evidence that Microbacterium sp. GM-1 can biologically induce calcification and suggest that strain GM-1 may play a potential role in the synthesis of new biominerals and in bioremediation or biorecovery. 相似文献
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Sheldon P. Gordon 《Journal of The Franklin Institute》1973,295(4):293-315
The general mth order difference equation X(n+m)+a1X(n+m?1)+…+amX(n) = F[n,X(n),…,X(n+m?1)] is considered. The stability properties of its solutions are studied using the discrete form of Liapunov's direct method. A quadratic form is selected as a possible Liapunov function V(n,X) and a scheme is developed for determining appropriate conditions on this function to insure that its total difference ΔV(n,X) is negative semi-definite or negative definite with respect to the difference equation. The approach is applied to the fourth-order difference equation in full detail to illustrate the method for determining the conditions which imply either uniform stability or uniform asymptotic stability and specific results are obtained. Several comments on, and extensions of, the work done by Puri and Drake for the cases m = 2 and m = 3 are presented.The results of the present approach in the homogeneous case where F[n,X(n),…,X(n+m?1)] = 0 are compared with the usual Schur-Cohn criteria and are shown to be at least as good. 相似文献
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BackgroundFragrance is one of the most important quality traits in rice, and the phenotype is attributed to the loss-of-function betaine aldehyde dehydrogenase (BADH2) gene. At least 12 allelic variations of BADH2 have been identified, and some of these have been applied to rice fragrance breeding using traditional molecular markers and Sanger sequencing techniques. However, these traditional methods have several limitations, such as being very expensive, imprecise, inefficient, and having security issues. Thus, a new molecular marker technology must be developed to improve rice fragrance breeding.ResultsIn this study, more than 95% of the cultivated fragrant rice varieties belonged to a 7-bp deletion in exon 2 (badh2-E2) or an 8-bp deletion and 3-bp variation in exon 7 (badh2-E7). Both allelic variations resulted in the loss of function of the badh2 gene. We developed two novel SNP molecular markers, SNP_badh2-E2 and SNP_badh2-E7, related to the alleles. Their genotype and phenotype were highly cosegregated in the natural variation of rice accessions, with 160 of the 164 fragrant rice varieties detected with the two markers. These markers cosegregated with the fragrance phenotype in the F2 population.ConclusionsTwo functional SNP molecular markers of badh2-E2 and badh2-E7 allelic variations were developed. These functional SNP molecular markers can be used for genotype and genetic improvement of rice fragrance through marker-assisted selection and will significantly improve the efficiency of fragrant rice breeding and promote commercial molecular breeding of rice in the future.How to cite: Li W, Zeng X, Li S, et al. Development and application of two novel functional molecular markers of BADH2 in rice. Electron J Biotechnol 2020;46. https://doi.org/10.1016/j.ejbt.2020.04.004. 相似文献