Development Of Disease Symptoms Research Articles

MicroRNAs in Vitis vinifera cv. Chardonnay Are Differentially Expressed in Response to Diaporthe Species.

Diaporthe species are important pathogens, saprobes, and endophytes on grapevines. Several species are known, either as agents of pre- or post-harvest infections, as causal agents of many relevant diseases, including swelling arm, trunk cankers, leaf spots, root and fruit rots, wilts, and cane bleaching. A growing body of evidence exists that a class of small non-coding endogenous RNAs, known as microRNAs (miRNAs), play an important role in post-transcriptional gene regulation, during plant development and responses to biotic and abiotic stresses. In this study, we explored differentially expressed miRNAs in response to Diaporthe eres and Diaporthe bohemiae infection in Vitis vinifera cv. Chardonnay under in vitro conditions. We used computational methods to predict putative miRNA targets in order to explore the involvement of possible pathogen response pathways. We identified 136 known and 41 new miRNA sequence variants, likely generated through post-transcriptional modifications. In the Diaporthe eres treatment, 61 known and 17 new miRNAs were identified while in the Diaporthe bohemiae treatment, 101 known and 21 new miRNAs were revealed. Our results contribute to further understanding the role miRNAs play during plant pathogenesis, which is possibly crucial in understanding disease symptom development in grapevines infected by D. eres and D. bohemiae.

The Malvastrum Yellow Vein Virus C4 Protein Promotes Disease Symptom Development and Enhances Virus Accumulation in Plants.

The begomovirus C4 protein is required for disease symptom development during virus infection in host plants. It can reprogram the cell cycle process for more efficient virus accumulation. In this study, we showed that the Malvastrum yellow vein virus (MaYVV) C4 protein could cause leaf up-ward curling and flower malformation, and increase virus accumulation in plants using PVX-based transient expression technology. We also demonstrated that, in the presence of its cognate betasatellite DNA (MaYVB), a mutant MaYVV, defective in producing the C4 protein (MaYVVΔC4), caused and alleviated infection in Nicotiana benthamiana. Transgenic plants expressing the MaYVV C4 protein showed upward leaf curling and uneven leaf lamina growth. Microscopic analysis showed that the epidermal cells of the C4 transgenic leaves were much smaller than those in the wild type (WT) leaves, and the mesophyll cells size and arrangement of transgenic plants was significantly altered. Inoculation of C4 transgenic plants with MaYVV or MaYVVΔC4 alone or associated with MaYVB showed that the transgenic C4 protein could promote viral and betasatellite accumulation and rescue the accumulation defect of MaYVVΔC4. Other transient expression assays also confirmed that the MaYVV C4 protein could suppress silencing of a GFP gene. In summary, our results indicate that the MaYVV C4 protein is a determinant of disease symptom and viral DNA accumulation. This protein can also function as a suppressor of RNA silencing and alter cell division and expansion.

A Novel Effector Protein of Apple Proliferation Phytoplasma Disrupts Cell Integrity of Nicotiana spp. Protoplasts.

Effector proteins play an important role in the virulence of plant pathogens such as phytoplasma, which are the causative agents of hundreds of different plant diseases. The plant hosts comprise economically relevant crops such as apples (Malus × domestica), which can be infected by ‘Candidatus Phytoplasma mali’ (P. mali), a highly genetically dynamic plant pathogen. As the result of the genetic and functional analyses in this study, a new putative P. mali effector protein was revealed. The so-called “Protein in Malus Expressed 2” (PME2), which is expressed in apples during P. mali infection but not in the insect vector, shows regional genetic differences. In a heterologous expression assay using Nicotiana benthamiana and Nicotiana occidentalis mesophyll protoplasts, translocation of both PME2 variants in the cell nucleus was observed. Overexpression of the effector protein affected cell integrity in Nicotiana spp. protoplasts, indicating a potential role of this protein in pathogenic virulence. Interestingly, the two genetic variants of PME2 differ regarding their potential to manipulate cell integrity. However, the exact function of PME2 during disease manifestation and symptom development remains to be further elucidated. Aside from the first description of the function of a novel effector of P. mali, the results of this study underline the necessity for a more comprehensive description and understanding of the genetic diversity of P. mali as an indispensable basis for a functional understanding of apple proliferation disease.

Biological control of Paecilomyces formosus, the causal agent of dieback and canker diseases of pistachio by two strains of Streptomyces misionensis

Dieback and canker of pistachio shoots and limbs is a commercially significant disease in Iran. Paecilomyces formosus (Sakag., May., Inoue and Tada) Houbraken & Samson is considered as the major causal agent of this malady. Actinomycetes and particularly members of the genus Streptomyces are well known as biocontrol agents for many plant diseases; they achieve this by production of bioactive metabolites and hydrolytic enzymes. The present study aimed to exploit Streptomyces isolates to biologically control P. formosus in vitro and in greenhouse experiments. Fifty two actinomycetes isolates were evaluated for their antagonistic effect against P. formosus isolated from diseased orchards. Considering their in vitro antagonistic performance, two isolates, designated as BH4-1 and BH4-3 were selected for molecular identification and in vivo experiment to be evaluated for biocontrol efficacy. Partial sequences of 16S rDNA unveiled their identity as two strains of Streptomyces misionensis with 99.9% sequence homology. For in vivo greenhouse experiments, inoculation of artificially made wounds on pistachio young trees stems performed with spore suspensions and culture extracts of either of the two bioactive S. misionensis Cercos et al. strains alone and/or together with P. formosus spore suspensions. Cupravit® was used as fungicide control. To evaluate the effect of the biocontrol test agents on the development of disease symptoms and severity, after about nine months, canker severity score, length and width of internal discolored lesions and frequency of P. formosus re-isolation from lesion margins were measured. The recorded disease criteria for treatments receiving S. misionensis strains were significantly in favor of bio-controlling the disease compared to the controls.

Environmental and irrigation conditions can mask the effect of Magnaporthiopsis maydis on growth and productivity of maize

Maize production in temperate countries is threatened by late wilt, caused by Magnaporthiopsis maydis. Plant infection occurs early after sowing, but symptoms appear from flowering onwards. The disease is mainly controlled by genetic resistance, which is often partially expressed in the field. Development of disease symptoms is also highly dependent on environmental conditions. This study looked at whether production and growth of susceptible maize are affected by M. maydis under environmental conditions that are suboptimal for disease development. In addition, the effect of water availability on disease development under optimal conditions was determined. Pot experiments were conducted in an open‐air enclosure in 2013, 2015 and 2016. Under unfavourable conditions for disease (low air temperature and relatively high air humidity), aboveground symptoms did not appear in the plants despite growth and production variables being clearly altered by the fungus. When air temperatures and humidity were optimal for disease development (air temperatures relatively high and humidity rather low), leaf symptoms on inoculated plants became apparent but with secondary importance compared to decreases in growth and production. The pathogen also affected the root:aboveground biomass ratio to a greater extent when the plants were under good water conditions than under deficit irrigation. Under optimal conditions and with good soil water content, the infected crop may end its cycle without symptoms, with the disease undetected, although reductions in yield and aboveground biomass can occur.

ВЛИЯНИЕ ФЕНОЛЬНЫХ СОЕДИНЕНИЙ РАСТЕНИЙ НА ПРОДУКЦИЮ ЭКЗОПОЛИСАХАРИДОВ БАКТЕРИЯМИ ERWINIA AMYLOVORA

Fire blight is a contagious disease affecting a wide range of host species within the family Rosaceae. The causal pathogen is Erwinia amylovora that belongs to the family Enterobacteriaceae. Many virulence determinants of E. amylovora have been characterized, including the Type III secretion system (T3SS), exopolysaccharides (EPS) amylovoran and levan. Amylovoran is a heteropolysaccharide with pentasaccharide repeating units containing four galactose and one glucuronic acid residues. Amylovoran is a pathogenicity factor in Erwinia amylovora, essential for the development of disease symptoms. It has been suggested to play a major role in disturbance and obstruction of the plant vascular system. Amylovoran and levan are required for biofilm formation by E.amylovora. In this study the following strains were used: Erwinia amylovora E2, D4. We demonstrate the influence of plant phenolic compounds on the production of E. amylovora EPS amylovoran and levan and catechol 2.3-dioxygenase activity. We showed that amylovoran production in presence in cultivation medium of cinnamic, vanillic and ferulic acids increased significantly (52.7%, 54.31% and 29.4% respectively). The presence in cultivation medium of caffeic acid did not influence amylovoran synthesis. Also we investigated that catechol 2.3-dioxygenase activity and amylovoran production was inhibited by salicylic acid (51% and 60% respectively). Unfortunately, we couldn’t demonstrate the influence of phenolic acids on levan production. The results indicate that plant phenolic compounds inhibit or increase amylovoran biosynthesis, however, it deserve further research.

MUTU BUAH JERUK KALAMANSI PADA BERBAGAI TINGKAT SERANGAN PENYAKIT KUDIS

[FRUIT QUALITIES OF CALAMANSI UNDER DIFFERENT SCAB DISEASE SEVERITIES]. Citrus scab caused by Elsinoe fawcettii dan Elsinoe australis fungi is an important disease for calamansi lime. The pathogen can result creamy-yellowish, raised, rounded, corky scabs appear on the rind surface of the fruit that reduces marketabilityof the fruit. The objective of this study was to evaluate the development and intensity of scab and their effects on the physical and chemical qualities of calamansi fruits. The observations were made on 30 fruit samples collected from farmer’s calamansi orchard for the development and intensity of disease symptoms, fruit appearances, juice content, and total soluble solids of the juice. The results showed that the pathogen began to attack on early fruit set phase. The intensity of the disease at the beginning of the observation was 11.06% and increased to 58.18% with an average rate of attack intensity of 14.54%. The disease reduced the fruit weight, fruit diameter, juice volume and total soluble solid levels.

Homologues of the RNA binding protein RsmA in Pseudomonas syringae pv. tomato DC3000 exhibit distinct binding affinities with non‐coding small RNAs and have distinct roles in virulence

Summary Pseudomonas syringae pv. tomato DC3000 (PstDC3000) contains five RsmA protein homologues. In this study, four were functionally characterized, with a focus on RsmA2, RsmA3 and RsmA4. RNA electrophoretic mobility shift assays demonstrated that RsmA1 and RsmA4 exhibited similar low binding affinities to non‐coding small RNAs (ncsRNAs), whereas RsmA2 and RsmA3 exhibited similar, but much higher, binding affinities to ncsRNAs. Our results showed that both RsmA2 and RsmA3 were required for disease symptom development and bacterial growth in planta by significantly affecting virulence gene expression. All four RsmA proteins, especially RsmA2 and RsmA3, influenced γ‐amino butyric acid utilization and pyoverdine production to some degree, whereas RsmA2, RsmA3 and RsmA4 influenced protease activities. A single RsmA, RsmA3, played a dominant role in regulating motility. Furthermore, reverse transcription quantitative real‐time PCR and western blot results showed that RsmA proteins, especially RsmA2 and RsmA3, regulated target genes and possibly other RsmA proteins at both transcriptional and translational levels. These results indicate that RsmA proteins in PstDC3000 exhibit distinct binding affinities to ncsRNAs and have distinct roles in virulence. Our results also suggest that RsmA proteins in PstDC3000 interact with each other, where RsmA2 and RsmA3 play a major role in regulating various functions in a complex manner.

Changes in PR2 and PAL Patterns in Barley Challenged with Leaf Stripe (Pyrenophora graminea) and Powdery Mildew (Blumeria graminis) Diseases

The seed-borne (Pyrenophora graminea; Pg) and foliar (Blumeria graminis; Bg) are two economically important fungal pathogens of barley worldwide. Barley plant resistance genes, as the pathogenesis related proteins play an important role in defense mechanisms. This study aimed to monitor the expression of PR2 and PAL pathogenesis related genes during compatible/incompatible barley interaction with Pg and Bg at different time points of disease development using the Quantitative Real-time PCR technique (qRT-PCR). Comparison of data showed that PR2 and PAL were significantly over expressed in infected resistant and susceptible plants as against their lower expression in controls,. Upregulation of these defense-related genes during Pg and Bg infections was companied with a slow development of disease symptoms at the time course in the resistant genotype. qRT-PCR analysis revealed higher gene expression in resistant barley plants inoculated with Pg as compared with Bg, with a maximum expression for PR2 (13.8 and 5.06-fold) and PAL (14.8 and 4.51-fold) respectively, at the latest stage of each disease development. It was also noteworthy that PR2 and PAL genes, had higher constitutive expression and faster induction for the both pathogens in the resistant genotype as compared with the susceptible one. Obtained results suggest that both genes, PR2 and PAL, positively regulate Pg- and Bg-resistance in barley plants during disease progress. These expression patterns can provide useful insights to better understanding of the barley–fungus interactions with different fungal lifestyles.

The Arabidopsis altered in stress response2 is Impaired in Resistance to Root and Leaf Necrotrophic Fungal Pathogens.

The Arabidopsis thaliana Glutathione S-transferase Phi8 (GSTF8) gene is recognised as a marker for early defence and stress responses. To identify regulators of these responses, a forward genetic screen for Arabidopsis mutants with up-regulated GSTF8 promoter activity was conducted by screening a mutagenized population containing a GSTF8 promoter fragment fused to the luciferase reporter gene (GSTF8:LUC). We previously identified several enhanced stress response (esr) mutants from this screen that conferred constitutive GSTF8:LUC activity and increased resistance to several pathogens and/or insects pests. Here we identified a further mutant constitutively expressing GSTF8:LUC and termed altered in stress response2 (asr2). Unlike the esr mutants, asr2 was more susceptible to disease symptom development induced by two necrotrophic fungal pathogens; the root pathogen Fusarium oxysporum, and the leaf pathogen Alternaria brassicicola. The asr2 allele was mapped to a 2.1 Mbp region of chromosome 2 and narrowed to four candidate loci.

Screening of a multi-virus resistant RNAi construct in cowpea through transient vacuum infiltration method.

Plant viruses are the most devastating pathogens causing substantial economic losses in many crops. Current viral disease management relies on prophylactics, roguing and insect vector control, since in most crops resistant gene pools for resistance breeding are unavailable. RNA interference, a sequence dependent gene silencing mechanism holds great potential in imparting virus resistance. In this study, the efficacy of a RNAi gene construct developed against four viruses commonly infesting tomato and chilli viz., capsicum chlorosis virus, groundnut bud necrosis virus, cucumber mosaic virus and chilli veinal mottle virus was evaluated. A 3546bp dsRNA-forming construct comprising sense-intron-antisense fragments in binary vector pBI121 (hpRNAi-MVR) was mobilized into Agrobacterium tumefaciens. Cowpea (Vigna unguiculata) was used as an indicator plant for GBNV agroinfiltration to evaluate the efficacy of hpRNAi-MVR construct in conferring GBNV resistance. The type of agroinfiltration, bacterial concentration and incubation-temperatures were optimized. Vacuum infiltration of three pulses of 20-30s at 66.66kPa were effective than syringe infiltration. Of the five Agrobacterial concentrations, OD600 0.5 was more efficient. Incubation temperature of 31 ± 1°C was favorable for development of disease symptoms than 20 ± 1°C and 26 ± 1°C. ELISA revealed a 35% decline in viral load in hpRNAi-MVR infiltrated plants compared to vector control plants. Quantitative real time PCR results have shown a viral gene silencing to the extent of 930-990 folds in hpRNAi-MVR infiltrated plants compared to vector control. This approach is simple, rapid and efficient to screen the efficacy of RNAi constructs developed for the RNAi mediated plant virus management.

Zmeny druhového spektra fuzariózy klasov spôsobené fungicídmi

Fusarium head blight (FHB) is a dangerous disease of cereals in case of yield losses and mycotoxin production. The aim of this work was to estimate the influence of used fungicides on species spectrum associated with Fusarium head blight (FHB). The study was realised in Slovakia on winter wheat by natural infection of FHB. The ears were sprayed with fungicides at beginning of flowering. After development of disease symptoms, fungicide efficacy was estimated, and Fusarium species spectrum were isolated and determined in laboratory. The fungicide efficacy against FHB achieved 60.2 – 88.3 %. The highest effectivity was estimated by using of prothioconazole + tebuconazole and prothioconazole + fluoxastrobin, followed by dimoxystrobin + cyproconazole, metconazole, propiconazole + cyproconazole, and prochloraz + tebuconazole. F. graminearum was the most frequently isolated from the ears, followed by M. nivale, F. avenaceum, F. culmorum, and F. poae. Using of prothioconazole + tebuconazole, metconazole, prothioconazole + fluoxastrobin, and tebuconazole significantly decreased incidence of F. graminearum on infected ears. The incidence of M. nivale on ears was significantly increased by using of all fungicides in comparison with untreated control. The results suggest that the ear spraying by triazole fungicides could enhance the incidence of less susceptible Fusarium species in ears, especially M. nivale. The variability in fungicide efficacy of fungicides against FHB in agricultural praxis colud be affected besides multi-pathogen origin of FHB just by selective effect of fungicides on different Fusarium species.

Small RNA analysis reveals different profiles among ‘Candidatus Phytoplasma mali’ strains in Malus x domestica cultivar Golden Delicious in vitro plants

In plant hosts phytoplasmas were shown to affect the expression of a broad range of genes and RNA regulatory molecules acting at a post-transcriptional level and leading to changes in several metabolic pathways. Effector proteins secreted by phytoplasmas play a paramount role in the metabolic changes resulting in disease symptoms development. It is shown here that in ‘Candidatus Phytoplasma mali’-infected in vitro plants of Malus x domestica cultivar Golden Delicious another class of pathogen-derived molecules represented by small RNA can be detected through specific sequencing. The profiles obtained from seven different phytoplasma strains revealed differences that could be associated to their capacity to multiply in the plant host or due to differences in the expression level of the phytoplasma transcripts.

NtPR1a regulates resistance to Ralstonia solanacearum in Nicotiana tabacum via activating the defense-related genes

Pathogenesis-related proteins (PRs) are associated with the development of systemic acquired resistance (SAR) against further infection enforced by fungi, bacteria and viruses. PR1a is the first PR-1 member that could be purified and characterized. Previous studies have reported its role in plants’ resistance system against oomycete pathogens. However, the role of PR1a in Solanaceae plants against the bacterial wilt pathogen Ralstonia solanacearum remains unclear. To assess roles of NtPR1a in tobacco responding to R. solanacearum, we performed overexpression experiments in Yunyan 87 plants (a susceptible tobacco cultivar). The results illuminated that overexpression of NtPR1a contributed to improving resistance to R. solanacearum in tobacco Yunyan 87. Specifically speaking, NtPR1a gene could be induced by exogenous hormones like salicylic acid (SA) and pathogenic bacteria R. Solanacearum. Moreover, NtPR1a-overexpressing tobacco significantly reduced multiple of R. solanacearum and inhibited the development of disease symptoms compared with wild-type plants. Importantly, overexpression of NtPR1a activated a series of defense-related genes expression, including the hypersensitive response (HR)-associated genes NtHSR201 and NtHIN1, SA-, JA- and ET-associated genes NtPR2, NtCHN50, NtPR1b, NtEFE26, and Ntacc oxidase, and detoxification-associated gene NtGST1. In summary, our results suggested that NtPR1a-enhanced tobacco resistance to R. solanacearum may be mainly dependent on activation of the defense-related genes.

Seed-born Burkholderia glumae Infects Rice Seedling and Maintains Bacterial Population during Vegetative and Reproductive Growth Stage.

Rice world production is affected due to the growing impact of diseases such as bacterial panicle blight, produced by Burkholderia glumae. The pathogen-induced symptoms include seedling rot, grain rot and leaf-sheath browning in rice plants. It is currently recognized the entrance of this pathogen to the plant, from infected seeds and from environmental sources of the microorganism. However, it is still not fully elucidated the dynamics and permanence of the pathogen in the plant, from its entry until the development of disease symptoms in seedlings or panicles. In this work it was evaluated the infection of B. glumae rice plants, starting from inoculated seeds and substrates, and its subsequent monitoring after infection. Various organs of the plant during the vegetative stage and until the beginning of the reproductive stage, were evaluated. In both inoculation models, the bacteria was maintained in the plant as an endophyte between 1 × 101 and 1 × 105 cfu of B. glumae.g−1 of plant throughout the vegetative stage. An increase of bacterial population towards initiation of the panicle was observed, and in the maturity of the grain, an endophyte population was identified in the flag leaf at 1 × 106 cfu of B. glumae.g−1 fresh weight of rice plant, conducting towards the symptoms of bacterial panicle blight. The results found, suggest that B. glumae in rice plants developed from infected seeds or from the substrate, can colonize seedlings, establishing and maintaining a bacterial population over time, using rice plants as habitat to survive endophyticly until formation of bacterial panicle blight symptoms.

Evaluation of Malus gene bank resources with German strains of Marssonina coronaria using a greenhouse-based screening method

Marssonina coronaria is considered a threat to organic apple production in Central Europe. Since the application of fungicides is limited in organic production, breeding for resistance seems to be a promising strategy to manage the disease in the future. In this study, an artificial inoculation method similar to procedures used in apple scab greenhouse screenings was developed using German strains of the pathogen M. coronaria for evaluating 110 Malus domestica cultivars. The strains were morphologically and molecularly characterized and confirmed as M. coronaria. Symptom development was significantly influenced by incubation method, conidia concentration and point of inoculation, but not by leaf position and different water types used for inoculation. The success of inoculation and spread of the fungus on infected leaves were confirmed by conventional PCR. Moreover, there was a difference in development of disease symptoms between inoculations with conidia from in vitro grown strains (in vitro inoculum) and conidia from diseased leaves from the orchard (field inoculum) in a time dependent manner. These differences which were first found with the susceptible cultivar ‘Topaz’ after artificial inoculation with in vitro and field inoculum were confirmed on 20 more apple cultivars inoculated with different in vitro grown strains. In summary, all tested cultivars, including 21 which are scab-resistant, developed symptoms of this disease. Results from three years of investigation indicate a decrease in virulence of M. coronaria strains, when cultivated on artificial culture (growth)-media. Hence field inoculum is recommended for artificial greenhouse screenings for the evaluation of disease resistance in Malus genetic resources.

Molecular Profiling of Pierce's Disease Outlines the Response Circuitry of Vitis vinifera to Xylella fastidiosa Infection.

Pierce’s disease is a major threat to grapevines caused by the bacterium Xylella fastidiosa. Although devoid of a type 3 secretion system commonly employed by bacterial pathogens to deliver effectors inside host cells, this pathogen is able to influence host parenchymal cells from the xylem lumen by secreting a battery of hydrolytic enzymes. Defining the cellular and biochemical changes induced during disease can foster the development of novel therapeutic strategies aimed at reducing the pathogen fitness and increasing plant health. To this end, we investigated the transcriptional, proteomic, and metabolomic responses of diseased Vitis vinifera compared to healthy plants. We found that several antioxidant strategies were induced, including the accumulation of gamma-aminobutyric acid (GABA) and polyamine metabolism, as well as iron and copper chelation, but these were insufficient to protect the plant from chronic oxidative stress and disease symptom development. Notable upregulation of phytoalexins, pathogenesis-related proteins, and various aromatic acid metabolites was part of the host responses observed. Moreover, upregulation of various cell wall modification enzymes followed the proliferation of the pathogen within xylem vessels, consistent with the intensive thickening of vessels’ secondary walls observed by magnetic resonance imaging. By interpreting the molecular profile changes taking place in symptomatic tissues, we report a set of molecular markers that can be further explored to aid in disease detection, breeding for resistance, and developing therapeutics.

Environmental and inoculum effects on epidemiology of bacterial spot disease of stone fruits and development of a disease forecasting system

Bacterial spot disease of stone fruits, caused by Xanthomonas arboricola pv. pruni, is of high economic importance in the major stone-fruit-producing areas worldwide. A better understanding of disease epidemiology can be valuable in developing disease management strategies. The effects of weather variables (temperature and wet/dry period) on epiphytic growth of X. arboricola pv. pruni on Prunus leaves were analyzed, and the relationship between inoculum density and temperature on disease development was determined and modeled. The information generated in this study, performed under controlled environmental conditions, will be useful to develop a forecasting system for X. arboricola pv. pruni. Optimal temperature for growth of epiphytic populations ranged from 20 to 30 °C under leaf wetness. In contrast, multiplication of epiphytic populations was not only interrupted under low relative humidity (RH) (< 40%) at 25 °C, but also resulted in cell inactivation, with only 0.001% initial cells recovered after 72 h incubation. A significant effect of inoculum density on disease severity was observed and 106 CFU/ml was determined as the minimal infective dose for X. arboricola pv. pruni on Prunus. Infections occurred at temperatures from 15 to 35 °C, but incubation at 25 and 30 °C gave the shortest incubation periods (7.7 and 5.9 days respectively). A model for predicting disease symptom development was generated and successfully evaluated, based on the relationship between disease severity and the accumulated heat expressed in cumulative degree day (CDD). Incubation periods of 150, 175 and 280 CDD were required for 5, 10 and 50% of disease severity, respectively.

Потенциальные возможности применения нутрицевтических продуктов с целью пролонгирования ремиссии у пациентов с синдромом раздраженного кишечника

Aim of review. To summarize the modern data on pathogenesis of symptoms irritable bowel syndrome (IBS) symptoms, to present nutraceutical product «Standart zdorovya: GASTRO» as an agent for IBS remission maintenance. Summary. Recent data indicate essential changes of intestinal microbiota in IBS in comparison to healthy population. These changes may be associated to development of inflammatory processes of intestinal wall. Long-term inflammation may result in nociceptor hypersensitivity i.e. peripheral sensitization that in turn, lead to the central sensitization and indirectly - to gastrointestinal tract (GIT) motility disorders. Besides, change of intestinal microbiota may impact the development of emotional disorders (e.g.: impaired capacity of affected intestinal microbiota to produce neurotransmitters). Therefore, according to the results of available studies, intestinal microbiota changes in IBS is a key factor for the cascade of events including intestinal wall inflammation, changes of gastrointestinal motility, decreased threshold of gastrointestinal receptor sensitivity, as well as emotional disorders resulting in development of disease symptoms. Medical preparation for IBS remission induction and remission maintenance should possess probiotic/prebiotic and anti-inflammatory properties, reduce visceral sensitivity, normalize intestinal motility and modulate patients’ emotional sphere. Due to capacity of «Standart zdorovya: GASTRO» components to deliver above-listed effects it can be promising for administration in patients with IBS.

Two ancestral genes shaped the Xanthomonas campestris TAL effector gene repertoire.

Xanthomonas transcription activator-like effectors (TALEs) are injected inside plant cells to promote host susceptibility by enhancing transcription of host susceptibility genes. TALE-encoding (tal) genes were thought to be absent from Brassicaceae-infecting Xanthomonas campestris (Xc) genomes based on four reference genomic sequences. We discovered tal genes in 26 of 49 Xc strains isolated worldwide and used a combination of single molecule real time (SMRT) and tal amplicon sequencing to yield a near-complete description of the TALEs found in Xc (Xc TALome). The 53 sequenced tal genes encode 21 distinct DNA binding domains that sort into seven major DNA binding specificities. In silico analysis of the Brassica rapa promoterome identified a repertoire of predicted TALE targets, five of which were experimentally validated using quantitative reverse transcription polymerase chain reaction. The Xc TALome shows multiple signs of DNA rearrangements that probably drove its evolution from two ancestral tal genes. We discovered that Tal12a and Tal15a of Xcc strain Xca5 contribute together in the development of disease symptoms on susceptible B.oleracea var. botrytis cv Clovis. This large and polymorphic repertoire of TALEs opens novel perspectives for elucidating TALE-mediated susceptibility of Brassicaceae to black rot disease and for understanding the molecular processes underlying TALE evolution.