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Cicadella viridis (L.) and Evacanthus interruptus L. (Hemiptera: Cicadellidae) are two of the most important leafhopper pests worldwide. Identifying habitat suitability areas of these species could be useful for their management. This study used the MaxEnt model to predict the current and future global habitat suitability areas of these species based on distribution and associated environmental data. The model showed that isothermality and the mean temperature of the driest quarter of the year were the most important environmental factors affecting the distribution of C. viridis and E. interruptus. Europe and southern China are the current primary habitat suitability areas for the two species. The high habitat suitability areas for C. viridis are also concentrated in these areas, whereas the high habitat suitability areas for E. interruptus are mainly found in western Europe. Under future climate change scenarios, the area of the two species habitat suitability areas increases, and the high habitat suitability areas for C. viridis decrease. However, the high habitat suitability areas for E. interruptus increase in 2041–2060 shared socioeconomic pathways 585 (ssp585) but decrease in 2041–2060 and 2061–2080 shared socioeconomic pathways 126 (ssp126). It is necessary to develop measures to monitor these species within habitat suitability areas, especially in high habitat suitability areas, to reduce economic losses.

PmSESY, a new wheat powdery mildew resistance gene was characterized and genetically mapped to the terminal region of chromosome 1RL of wild rye Secale sylvestre. The genus Secale is an important resource for wheat improvement. The Secale species are usually considered as non-adapted hosts of Blumeria graminis f. sp. tritici (Bgt) that causes wheat powdery mildew. However, as a wild species of cultivated rye, S. sylvestre is rarely studied. Here, we reported that 25 S. sylvestre accessions were susceptible to isolate BgtYZ01, whereas the other five confer effective resistance to all the tested isolates of Bgt. A population was then constructed by crossing the resistant accession SESY-01 with the susceptible accession SESY-11. Genetic analysis showed that the resistance in SESY-01 was controlled by a single dominant gene, temporarily designated as PmSESY. Subsequently, combining bulked segregant RNA-Seq (BSR-Seq) analysis with molecular analysis, PmSESY was mapped into a 1.88 cM genetic interval in the terminus of the long arm of 1R, which was closely flanked by markers Xss06 and Xss09 with genetic distances of 0.87 cM and 1.01 cM, respectively. Comparative mapping demonstrated that the corresponding physical region of the PmSESY locus was about 3.81 Mb in rye cv. Lo7 genome, where 30 disease resistance-related genes were annotated, including five NLR-type disease resistance genes, three kinase family protein genes, three leucine-rich repeat receptor-like protein kinase genes and so on. This study gives a new insight into S. sylvestre that shows divergence in response to Bgt and reports a new powdery mildew resistance gene that has potential to be used for resistance improvement in wheat.

New powdery mildew resistance gene Pm68 was found in the terminal region of chromosome 2BS of Greek durum wheat TRI 1796. The co-segregated molecular markers could be used for MAS. Durum wheat (Triticum turgidum L. var. durum Desf.) is not only an important cereal crop for pasta making, but also a genetic resource for common wheat improvement. In the present study, a Greek durum wheat TRI 1796 was found to confer high resistance to all 22 tested isolates of Blumeria graminis f. sp. tritici (Bgt). Inheritance study on the F1 plants and the F2 population derived from the cross TRI 1796/PI 584832 revealed that the resistance in TRI 1796 was controlled by a single dominant gene, herein designated Pm68. Using the bulked segregant RNA-Seq (BSR-Seq) analysis combined with molecular analysis, Pm68 was mapped to the terminal part of the short arm of chromosome 2B and flanked by markers Xdw04 and Xdw12/Xdw13 with genetic distances of 0.22 cM each. According to the reference genome of durum wheat cv. Svevo, the corresponding physical region spanned the Pm68 locus was about 1.78-Mb, in which a number of disease resistance-related genes were annotated. This study reports the new powdery mildew resistance gene Pm68 that would be a valuable resource for improvement of both common wheat and durum wheat. The co-segregated markers (Xdw05–Xdw11) developed here would be useful tools for marker-assisted selection (MAS) in breeding.

Wheat powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is a devastating disease that threatens wheat production worldwide. Pm12, which originated from Aegilops speltoides, a wild relative of wheat, confers strong resistance to powdery mildew and therefore has potential use in wheat breeding. Using susceptible mutants induced by gamma irradiation, we physically mapped and isolated Pm12 and showed it to be orthologous to Pm21 from Dasypyrum villosum, also a wild relative of wheat. The resistance function of Pm12 was validated via ethyl methanesulfonate mutagenesis, virus-induced gene silencing, and stable genetic transformation. Evolutionary analysis indicates that the Pm12/Pm21 loci in wheat species are relatively conserved but dynamic. Here, we demonstrated that the two orthologous genes, Pm12 and Pm21, possess differential resistance against the same set of Bgt isolates. Overexpression of the coiled-coil domains of both PM12 and PM21 induces cell death in Nicotiana benthamiana leaves. However, their full-length forms display different cell death-inducing activities caused by their distinct intramolecular interactions. Cloning of Pm12 will facilitate its application in wheat breeding programs. This study also gives new insight into two orthologous resistance genes, Pm12 and Pm21, which show different race specificities and intramolecular interaction patterns.

New powdery mildew resistance gene Pm68 was found in the terminal region of chromosome 2BS of Greek durum wheat TRI 1796. The co-segregated molecular markers could be used for MAS. Durum wheat (Triticum turgidum L. var. durum Desf.) is not only an important cereal crop for pasta making, but also a genetic resource for common wheat improvement. In the present study, a Greek durum wheat TRI 1796 was found to confer high resistance to all 22 tested isolates of Blumeria graminis f. sp. tritici (Bgt). Inheritance study on the F

Herein, we utilize a facile hydrothermal process for the synthesis of Bi 2 S 3 films on the SnO 2 : F films (FTO) substrate. The structure, surface morphology and thickness of the samples were characterized by variously analysis method. The Bi 2 S 3 films-based laser detectors exhibit excellent linear photocurrent characteristics, good sensitivity to 450 nm, 650 nm and 850 nm laser beam. Prolonging the reaction time was beneficial for the photoelectric performance of the Bi 2 S 3 films-based laser detectors. The photoelectric conversion properties can be improved by optimizing the thickness of the films. The experimental results of this work can provide an additional opportunity for fabricating excellent photoconductive performance laser detectors.

Streptococcus mutans develops competence for genetic transformation through a complex network that receives inputs from at least two signaling peptides, competence-stimulating peptide (CSP) and sigX -inducing peptide (XIP). The key step of competence induction is the transcriptional activation of comX , which encodes an alternative sigma factor, SigX (σ X ), controlling the expression of late competence genes essential for DNA uptake and recombination. In this study, we provide evidence that MecA acts as a negative regulator in the posttranslational regulation of SigX in S. mutans . Using luxAB transcriptional reporter strains, we demonstrate that MecA represses the expression of late competence genes in S. mutans grown in a complex medium that is subpermissive for competence induction by CSP. The negative regulation of competence by MecA requires the presence of a functional SigX. Accordingly, inactivation of MecA results in a prolonged competence state of S. mutans under this condition. We have also found that the AAA+ protease ClpC displays a similar repressing effect on late competence genes, suggesting that both MecA and ClpC function coordinately to regulate competence in the same regulatory circuit in S. mutans . This suggestion is strongly supported by the results of bacterial two-hybrid assays, which demonstrate that MecA interacts with both SigX and ClpC, forming a ternary SigX-MecA-ClpC complex. Western blot analysis also confirms that inactivation of MecA or ClpC results in the intracellular accumulation of the SigX in S. mutans . Together, our data support the notion that MecA mediates the formation of a ternary SigX-MecA-ClpC complex that sequesters SigX and thereby negatively regulates genetic competence in S. mutans .

Quorum sensing activation by signal pheromone (CSP) in Streptococcus mutans depends on the membrane-associated receptor ComD, which senses the signal and triggers the signaling cascade for bacteriocin production and other cell density-dependent activities. However, the mechanism of the signal recognition via the ComD receptor in this species is nearly unexplored. Here, we show that the membrane domain of the ComD protein forms six transmembrane segments with three extracellular loops, loopA, loopB and loopC. By structural and functional analyses of these extracellular loops, we demonstrate that both loopC and loopB are required for CSP recognition, while loopA plays little role in CSP detection. A deletion or substitution mutation of four residues NVIP in loopC abolishes CSP recognition for quorum sensing activities. We conclude that both loopC and loopB are required for forming the receptor and residues NVIP of loopC are essential for CSP recognition and quorum sensing activation in S. mutans.

Background: In Streptococcus mutans, ComCDE, a peptide-induced two-component signal transduction system, forms a closed signal transduction, and even if difunctional ComE closes this signal at its headstream to avoid its infinite amplification, it is not enough for ComE to work in a concentration-dependent manner. CslAB has a chance to regulate ComCDE by controlling extracellular competence-stimulating peptide (CSP) concentration through its processing and secretion. Objectives: To first confirm the binding properties of cslAB promoter (PcslAB) with ComE, then to uncover in vivo need of cslAB expression, and finally to unveil the role of CslAB. Materials and Methods: Electrophoretic mobility shift assay was used to confirm the binding properties of PcslAB with ComE. In vivo cslAB transcription was detected by β-galactosidase activity because its gene has been fused to cslAB operon, and finally the role of CslAB was reviewed. Results: PcslAB is a weak promoter responding to ComE and its binding appears to be negative cooperative. Although PcslAB is partially controlled by ComCDE, it can respond to ComCDE regulation. Supported by the obtained molecular evidence, CslAB acts as a stabilizer of ComCDE signal on the patterns of its expression. Conclusions: PcslAB is partially controlled by ComCDE. CslAB is a stabilizer of ComCDE signal to ensure that ComE works in a concentration-dependent manner.

The receptor for human endothelial differentiation gene-1 protein (EDG-1) was C-terminally tagged with green fluorescent protein and expressed in the methylotrophic yeast, Pichia pastoris. EDG-1 expression was driven by the highly inducible alcohol oxidase 1 promoter. Expression of EDG-1 recombinant protein was detected by Western blot analysis and confocal microscopy. The recombinant EDG-1 receptor protein was located in the plasma membrane. Radioligand binding assays demonstrated that the EDG-1 receptors expressed in Pichia pastoris have specific and saturation binding of (32)P-labeled sphingosine 1-phosphate.

The human bradykinin B2 receptor (B2R) fused with green fluorescent protein (GFP) at the C-terminal has been expressed in the methylotrophic yeast Pichia pastoris. In the expression vector, B2R gene was driven under the highly inducible promoter of alcohol oxidase 1 gene of P. pastoris. By fluorescence activated cell sorting (FACS) analysis and Western blot analysis, it was proved that B2R recombinant receptor proteins were expressed at a high level in the yeast. Furthermore, the transformants of P. pastoris were monitored with confocal microscopy, a strong green fluorescence was checked out. The recombinant B2R receptor proteins were mainly located on the plasma membrane proved by immunofluorescence microscopy.

Analysis of mutants and clone of genes is crucial for unraveling the mechanism of anther development. The lack of elongation of siliques in a novel shortened early-stage siliques (ses) mutant was caused by unsuccessful pollination because of aborted pollens. At stage 11, microspores of mutantses appeared weakly stained and degenerated. At stage 14, mutantses produced abnormal pollens, and the anther wall was collapsed and crumpled; furthermore, some cavities were also found under the epidermis. Mutantses showed that the gene responsible for the defects plays a role in anther development. By mapping, mutantses was narrowed into a 67-kb interval on chromosome 1 between CER448792 (2,000,541 bp) and CER464544 (2,067,844 bp). By using the sequence-based map ofArabidopsis genes with mutant phenotypes,ses was localized on the right of phenotype marker AT1g06150 and on the left of phenotype marker AT1g08060. The phenotyping and mapping data both pointed to the conclusion thatses was a novel mutant related to anther development. Sequencing showed that there was a point mutation in gene AT1G06710.1; thus, gene AT1G06710.1 is the mist likely candidate gene responsible for the mutation.

Seeds acquire primary dormancy during their development and the phytohormone abscisic acid (ABA) is known to play a role in inducing the dormancy. qSD12 is a major seed dormancy quantitative trait locus (QTL) identified from weedy rice. This research was conducted to identify qSD12 candidate genes, isolate the candidates from weedy rice, and determine the relation of the dormancy gene to ABA. A fine mapping experiment, followed by marker-assisted progeny testing for selected recombinants, narrowed down qSD12 to a genomic region of

Many species of streptococci secrete and use a competence-stimulating peptide (CSP) to initiate quorum sensing for induction of genetic competence, bacteriocin production, and other activities. These signaling molecules are small, unmodified peptides that induce powerful strain-specific activity at nano-molar concentrations. This feature has provided an excellent opportunity to explore their structure–function relationships. However, CSP variants have also been identified in many species, and each specifically activates its cognate receptor. How such minor changes dramatically affect the specificity of these peptides remains unclear. Structure–activity analysis of these peptides may provide clues for understanding the specificity of signaling peptide–receptor interactions. Here, we use the Streptococcus mutans CSP as an example to describe methods of analyzing its structure–activity relationship. The methods described here may provide a platform for studying quorum-sensing signaling peptides of other naturally transformable streptococci.