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During the nationwide survey of fire blight, the typical shoot blight symptoms were found on Korean mountain ash (Sorbus alnifolia) which was located near an orchard that produced fire blight on pear trees in Eumseong, Korea, May 2021. To identify the causal agent, we progressed isolation from the symptomatic leaves and shoots. Two white and mucoid colonies were isolated into the pure culture. Two isolates were identified as Erwinia amylovora according to the colony–polymerase chain reaction (PCR) with amsB primers and the phylogenetic tree using 16S rRNA sequences. To test of pathogenicity of two isolates, we inoculated immature pear fruits and understock of apple. We observed necrosis and oozes on immature pear fruits and shoot blight resulting in necrosis on apple shoots six days after inoculation. Colonies were recovered from the inoculated pears and apples, and identity was confirmed through colony PCR for amsB genes. To our knowledge, E. amylovora was first reported on Korean mountain ash native to South Korea.

Genetic and environmental cues affecting seed microbial communities have been investigated to assess the ecological characteristics of seed microbial communities. However, little is known concerning seed-to-seed microbial variations and ecological drivers at the single-seed level. We report rare taxa-associated heterogeneity and robustness of seed bacterial and fungal communities in individual seeds using 63 pooled and 70 single-seed samples from a single field-grown rice plant. Ordination analyses showed that seed-to-seed variation patterns could be clustered according to the originating panicle branch. Bacterial-fungal associations and in silico extinction experiments demonstrated that rare taxa contribute to the connectivity and robustness of the associations. Null modeling-based statistical analysis revealed that the distribution of rare taxa is mainly governed by dispersal limitation, whereas the distribution of prevalent taxa is mainly governed by homogeneous selection and ecological drift. Our findings provide an ecological framework for understanding the heterogeneity of seed microbial communities in a single plant; they will facilitate the development and application of seed microbiota or single microbe-based engineering strategies.

Plants possess effective immune systems that defend against most microbial attackers. Recent plant immunity research has focused on the classic binary defense model involving the pivotal role of small-molecule hormones in regulating the plant defense signaling network. Although most of our current understanding comes from studies that relied on information derived from a limited number of pathosystems, newer studies concerning the incredibly diverse interactions between plants and microbes are providing additional insights into other novel mechanisms. Here, we review the roles of both classical and more recently identified components of defense signaling pathways and stress hormones in regulating the ambivalence effect during responses to diverse pathogens. Because of their different lifestyles, effective defense against biotrophic pathogens normally leads to increased susceptibility to necrotrophs, and vice versa. Given these opposing forces, the plant potentially faces a trade-off when it mounts resistance to a specific pathogen, a phenomenon referred to here as the ambivalence effect. We also highlight a novel mechanism by which translational control of the proteins involved in the ambivalence effect can be used to engineer durable and broad-spectrum disease resistance, regardless of the lifestyle of the invading pathogen.

Erwinia amylovora, a causal bacterium of fire blight disease, is registered as a prohibited quarantine pathogen in Korea. To control the disease, the government should diagnose the disease, dig and bury the host trees when fire blight occurs. Fire blight was the first reported in 43 orchards of Anseong, Cheonan, and Jecheon in 2015, and 42.9 ha of host trees were eradicated. However, the disease spread to eleven cities, so that 348 orchards and 260.4 ha of host trees were eradicated until 2019. Fire blight of Asian pear occurred mainly in the southern part of Gyeonggi, and Chungnam province, on average of 29±9.2 orchards per year. And the age of the infected trees were mostly 20-30 years old. In apple trees, the disease occurred mainly in the northern part of Gyeonggi, Gangwon, and Chungbuk province, on average of 41±57.6 orchards per year, increased highly in 2018 and 2019. The age of infected apple trees were under 20 years old. Therefore, because the disease spread rapidly in young apple trees, spraying control agents to the trees in a timely manner and removing infected trees quickly are important to prevent the spread of fire blight in the orchard of immature trees.

The genome of the rice blast fungus Magnaporthe oryzae contains several types of transposable elements (TEs), and some TEs cause genetic variation that allows M. oryzae to evade host detection. We studied how five abundant TEs in rice pathogens, Pot3, Pot2, MAGGY, Line-like element (MGL) and Mg-SINE, are expressed under diverse conditions related to growth, development, and stress. Expression of Pot3 and Pot2 was activated in germinated conidia and mycelia treated with tricyclazole. Retrotransposon MAGGY was highly expressed in appressoria and tricyclazole-treated mycelia. MAGGY and Pot2 were also activated during the early and late stages of perithecia development. MGL was up-regulated in conidia and during conidial germination but not during appressorium formation. No noticeable expression of Mg-SINE was observed under most conditions. Our results should help investigate if and how condition-specific expressions of some TEs contribute to the biology and evolution of M. oryzae.

Because pathogens use diverse infection strategies, plants cannot use one-size-fits-all defence and modulate defence responses based on the nature of pathogens and pathogenicity mechanism. Here, we report that a rice glycoside hydrolase (GH) plays contrasting roles in defence depending on whether a pathogen is hemibiotrophic or necrotrophic. The Arabidopsis thaliana MORE1 (Magnaporthe oryzae resistance 1) gene, encoding a member of the GH10 family, is needed for resistance against M. oryzae and Alternaria brassicicola, a fungal pathogen infecting A. thaliana as a necrotroph. Among 13 rice genes homologous to MORE1, 11 genes were induced during the biotrophic or necrotrophic stage of infection by M. oryzae. CRISPR/Cas9-assisted disruption of one of them (OsMORE1a) enhanced resistance against hemibiotrophic pathogens M. oryzae and Xanthomonas oryzae pv. oryzae but increased susceptibility to Cochliobolus miyabeanus, a necrotrophic fungus, suggesting that OsMORE1a acts as a double-edged sword depending on the mode of infection (hemibiotrophic vs. necrotrophic). We characterized molecular and cellular changes caused by the loss of MORE1 and OsMORE1a to understand how these genes participate in modulating defence responses. Although the underlying mechanism of action remains unknown, both genes appear to affect the expression of many defence-related genes. Expression patterns of the GH10 family genes in A. thaliana and rice suggest that other members also participate in pathogen defence.

Rice panicle blast occurred severely in southern provinces of Korea in 2014. The proportion of panicle blast incidence area to cultivated area of rice were 11.0% and 14.6% in Jeollanam-do and Gyeongsangnam-do, respectively. To identify the causal factors of the outbreak, we investigated weather conditions in August, amount of cultivated area of mainly grown cultivars, and nitrogen contents in plants with different disease incidences in 2014. ‘Saenuri,’ ‘Ilmibyeo,’ ‘Unkwang,’ ‘Dongjin 1 ho,’ ‘Nampyeongbyeo,’ and ‘Hwangkeumnuri’ were mainly grown cultivars. Monthly average of daily air temperature in August 2014 was 3.2°C and 3.1°C less than 2018 in Haenam and Miryang, respectively. Rainfall in August 2014 was 70.0% and 42.0% greater than 2018 in Haenam and Miryang, respectively. The numbers of blast warning days in August calculated nationwide using a forecast model for blast infection were higher in 2014 than in 2018, and they were in high level throughout the country in 2014. Nitrogen contents in plant samples from high-incidence plots were significantly higher than those from low-incidence plots. Consequently, excessive use of nitrogen fertilizers was the main factor for the disease outbreak at the level of specific farms, in addition to the collective cultivation of susceptible cultivar, low temperatures and frequent rainfalls in August.

The fungus Daldinia childiae strain JS-1345, isolated from stem tissue of Abies koreana (Korean fir), has shown strong anti-inflammatory activity. Here, we report the genome sequence of D. childiae JS-1345. The final assembly consisted of 133 scaffolds totaling 38,652,569 bp (G+C content, 44.07%).

The fungus Aspergillus oryzae strain BP2-1 was isolated from the traditional malted starter culture nuruk. We report here the draft whole-genome sequence of A. oryzae BP2-1, which is comprised of 14 scaffolds with a total length of 39,455,382 bp and a GC content of 47.13%.

Amongst the various post‐translational modifications (PTMs), SUMOylation is a conserved process of attachment of a small ubiquitin‐related modifier (SUMO) to a protein substrate in eukaryotes. This process regulates many important biological mechanisms, including transcriptional regulation, protein stabilization, cell cycle, DNA repair and pathogenesis. However, the functional role of SUMOylation is not well understood in plant‐pathogenic fungi, including the model fungal pathogen Magnaporthe oryzae. In this study, we elucidated the roles of four SUMOylation‐associated genes that encode one SUMO protein (MoSMT3), two E1 enzymes (MoAOS1 and MoUBA2) and one E2 enzyme (MoUBC9) in fungal development and pathogenicity. Western blot assays showed that SUMO modification was abolished in all deletion mutants. MoAOS1 and MoUBA2 were mainly localized in the nucleus, whereas MoSMT3 and MoUBC9 were localized in both the nucleus and cytoplasm. However, the four SUMOylation‐associated proteins were predominantly localized in the nucleus under oxidative stress conditions. Deletion mutants for each of the four genes were viable, but showed significant defects in mycelial growth, conidiation, septum formation, conidial germination, appressorium formation and pathogenicity. Several proteins responsible for conidiation were predicted to be SUMOylated, suggesting that conidiation is controlled at the post‐translational level by SUMOylation. In addition to infection‐related development, SUMOylation also played important roles in resistance to nutrient starvation, DNA damage and oxidative stresses. Therefore, SUMOylation is required for infection‐related fungal development, stress responses and pathogenicity in M. oryzae. This study provides new insights into the role of SUMOylation in the molecular mechanisms of pathogenesis of the rice blast fungus and other plant pathogens.

The fungus Amphirosellinia nigrospora strain JS-1675 has been reported to exert antimicrobial effects against various plant-pathogenic bacteria and fungi. Here, we report the draft genome sequence of A. nigrospora for the first time., The fungus Amphirosellinia nigrospora strain JS-1675 has been reported to exert antimicrobial effects against various plant-pathogenic bacteria and fungi. Here, we report the draft genome sequence of A. nigrospora for the first time. The assembly comprises 48,177,783 bp with 18 scaffolds.

The heart-specific isoform of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB2) is an important regulator of glycolytic flux in cardiac cells. Here, we present the crystal structures of two PFKFB2 orthologues, human and bovine, at resolutions of 2.0 and 1.8 A, respectively. Citrate, a TCA cycle intermediate and well-known inhibitor of PFKFB2, co-crystallized in the 2-kinase domains of both orthologues, occupying the fructose-6-phosphate binding-site and extending into the γ-phosphate binding pocket of ATP. This steric and electrostatic occlusion of the γ-phosphate site by citrate proved highly consequential to the binding of co-complexed ATP analogues. The bovine structure, which co-crystallized with ADP, closely resembled the overall structure of other PFKFB isoforms, with ADP mimicking the catalytic binding mode of ATP. The human structure, on the other hand, co-complexed with AMPPNP, which, unlike ADP, contains a γ-phosphate. The presence of this γ-phosphate made adoption of the catalytic ATP binding mode impossible for AMPPNP, forcing the analogue to bind atypically with concomitant conformational changes to the ATP binding-pocket. Inhibition kinetics were used to validate the structural observations, confirming citrate's inhibition mechanism as competitive for F6P and noncompetitive for ATP. Together, these structural and kinetic data establish a molecular basis for citrate's negative feed-back loop of the glycolytic pathway via PFKFB2. Proteins 2016; 85:117-124. © 2016 Wiley Periodicals, Inc.

a quarantine disease in Korea, was performed in November 2012. In the survey, ALS was observed in eighty eight farmers’ fields of Sukok, Jinju and Okjong, Hadong in Gyeongnam Province, and one field in Namwon of Jeollabuk Province. The infected field of Namwon closed immediately after the disease diagnosed ALS. In detailed survey of Sukok and Okjong areas during February 2012 to January 2015, ALS occurrence decreased from 45% farmer’s fields on December 2012 to 5% on January 2015, and from 38% on November 2013 to 5% on January 2015, respectively. Phenotypic characteristics of the Korean strains were similar to those of the type strain of

An endophytic fungus, Fusarium solani strain JS-169, isolated from a mulberry twig, showed considerable antifungal activity. Here, we report the draft genome sequence of this strain. The assembly comprises 17 scaffolds, with an N 50 value of 4.93 Mb. The assembled genome was 45,813,297 bp in length, with a G+C content of 49.91%.

The fungus Aspergillus persii strain NIBRFGC000004109 is capable of producing penicillic acid and showed antibacterial activity against various plant-pathogenic bacteria, including Xanthomonas arboricola pv. pruni. Here, we report the first draft whole-genome sequence of A. persii . The assembly comprises 38,414,373 bp, with 12 scaffolds.

An endophytic fungus, Gaeumannomyces sp. strain JS-464, is capable of producing a number of secondary metabolites which showed significant nitric oxide reduction activity. The draft genome assembly has a size of 53,151,282 bp, with a G+C content of 53.11% consisting of 80 scaffolds with an N 50 of 7.46 Mbp.

The fungus Raffaelea quercus-mongolicae is the causal agent of Korean oak wilt, a disease associated with mass mortality of oak trees (e.g., Quercus spp.). The fungus is vectored and dispersed by the ambrosia beetle, Platypus koryoensis . Here, we present the 27.0-Mb draft genome sequence of R. quercus-mongolicae strain KACC44405.

Whereas moderately increased cellular oxidative stress is supportive for cancerous growth of cells, excessive levels of reactive oxygen species (ROS) is detrimental to their growth and survival. We demonstrated that high ROS levels, via increased oxidized glutathione (GSSG), induce isoform-specific S-glutathionylation of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) at the residue Cys206, which is located near the entrance to the 6-phosphofructo-2-kinase catalytic pocket. Upon this ROS-dependent, reversible, covalent modification, a marked decrease in its catalytic ability to synthesize the Fructose-2,6-bisphosphate (Fru-2,6-P2), the key glycolysis allosteric activator, was observed. This event was coupled to a decrease in glycolytic flux and an increase in glucose metabolic flux into the pentose phosphate pathway (PPP). This shift, in turn, caused an increase in reduced glutathione (GSH) and, ultimately, resulted in ROS detoxification inside HeLa cells. The ability of PFKFB3 to control the Fru-2,6-P2 levels in an ROS-dependent manner allows the PFKFB3-expressing cancer cells to continue energy metabolism with a reduced risk of excessive oxidative stress and, thereby, to support their cell survival and proliferation. This study provides a new insight into the roles of PFKFB3 as switch that senses and controls redox homeostasis in cancer in addition to its role in cancer glycolysis.

The process of mating in Basidiomycota is regulated by homeodomain-encoding genes (HD) and pheromones and G protein-coupled pheromone receptor genes (P/R). Whether these genes are actually involved in determining mating type distinguishes mating systems that are considered tetrapolar (two locus) from bipolar (one locus). Polyporales are a diverse group of wood-decay basidiomycetes displaying high variability in mating and decay systems. Many of the bipolar species appear to be brown-rot fungi, and it has been hypothesized that there is a functional basis for this correlation. Here we characterize mating genes in recently sequenced Polyporales and other Agaricomycete genomes. All Agaricomycete genomes encode HD and pheromone receptor genes regardless of whether they are bipolar or tetrapolar. The HD genes are organized into a MAT-HD locus with a high degree of gene order conservation among neighboring genes, with the gene encoding mitochondrial intermediate peptidase consistently syntenic but no linkage to the P/R genes. To have a complete dataset of species with known mating systems we determined that Wolfiporia cocos appears to be bipolar, using the criterion that DNA polymorphism of MAT genes should be extreme. Testing the correlation of mating and decay systems while controlling for phylogenetic relatedness failed to identify a statistical association, likely due to the small number of taxa employed. Using a phylogenetic analysis of Ste3 proteins, we identified clades of sequences that contain no known mating type-specific receptors and therefore might have evolved novel functions. The data are consistent with multiple origins of bipolarity within the Agaricomycetes and Polyporales, although the alternative hypothesis that tetrapolarity and bipolarity are reversible states needs better testing.

This study was carried out to investigate yield loss due to soybean leaf spot disease caused by Cercospora sojina Hara and to determine the economic threshold level. The investigations revealed highly significant correlations between disease severity (diseased leaf area) and yield components (pod number per plant, total grain number per plant, total grain weight per plant, percent of ripened grain, weight of hundred seed, and yield). The correlation coefficients between leaf spot severity and each component were �0.90, �0.90, �0.92, �0.99, �0.90 and �0.94, respectively. The yield was inversely proportional to the diseased leaf area increased. The regression equation, yield prediction model, between disease severity (x) and yield (y) was obtained as y= �3.7213x + 354.99 (R 2 = 0.9047). Based on the yield prediction model, economic injury level and economic threshold level could be set as 3.3% and 2.6% of diseased leaf area of soybean.

The molecular basis of fructose-2,6-bisphosphatase (F-2,6-P(2)ase) of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB) was investigated using the crystal structures of the human inducible form (PFKFB3) in a phospho-enzyme intermediate state (PFKFB3-P•F-6-P), in a transition state-analogous complex (PFKFB3•AlF(4)), and in a complex with pyrophosphate (PFKFB3•PP(i)) at resolutions of 2.45, 2.2, and 2.3 Å, respectively. Trapping the PFKFB3-P•F-6-P intermediate was achieved by flash cooling the crystal during the reaction, and the PFKFB3•AlF(4) and PFKFB3•PP(i) complexes were obtained by soaking. The PFKFB3•AlF(4) and PFKFB3•PP(i) complexes resulted in removing F-6-P from the catalytic pocket. With these structures, the structures of the Michaelis complex and the transition state were extrapolated. For both the PFKFB3-P formation and break down, the phosphoryl donor and the acceptor are located within ~5.1 Å, and the pivotal point 2-P is on the same line, suggesting an "in-line" transfer with a direct inversion of phosphate configuration. The geometry suggests that NE2 of His253 undergoes a nucleophilic attack to form a covalent N-P bond, breaking the 2O-P bond in the substrate. The resulting high reactivity of the leaving group, 2O of F-6-P, is neutralized by a proton donated by Glu322. Negative charges on the equatorial oxygen of the transient bipyramidal phosphorane formed during the transfer are stabilized by Arg252, His387, and Asn259. The C-terminal domain (residues 440-446) was rearranged in PFKFB3•PP(i), implying that this domain plays a critical role in binding of substrate to and release of product from the F-2,6-P(2) ase catalytic pocket. These findings provide a new insight into the understanding of the phosphoryl transfer reaction.

Efforts toward improving the predictiveness in tier-based approaches to virtual screening (VS) have mainly focused on protein kinases. Despite their significance as drug targets, small molecule kinases have been rarely tested with these approaches. In this paper, we investigate the efficacy of a pharmacophore screening-combined structure-based docking approach on the human inducible 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase, an emerging target for cancer chemotherapy. Six out of a total 1364 compounds from NCI’s Diversity Set II were selected as true actives via throughput screening. Using a database constructed from these compounds, five programs were tested for structure-based docking (SBD) performance, the MOE of which showed the highest enrichments and second highest screening rates. Separately, using the same database, pharmacophore screening was performed, reducing 1364 compounds to 287 with no loss in true actives, yielding an enrichment of 4.75. When SBD was retested with the pharmacophore filtered database, 4 of the 5 SBD programs showed significant improvements to enrichment rates at only 2.5% of the database, with a 7-fold decrease in an average VS time. Our results altogether suggest that combinatorial approaches of VS technologies are easily applicable to small molecule kinases and, moreover, that such methods can decrease the variability associated with single-method SBD approaches.

Rice bakanae disease, caused by the fungus Fusarium fujikuroi, is one of the most important rice diseases anddistributed widely in Asia. Resistance screening system in rice field had been established. However, theevaluation results of the system vary according to the environmental conditions when the test is conducted. Todevelop precise and rapid evaluation method of disease resistance of rice to bakanae disease, in vitro screeningsystem was attempted in this study. The six cultivars namely, ‘Nampyeongbyeo’, ‘Junambyeo’,‘Chucheongbyeo’, ‘Samcheonbyeo’, ‘Odaebyeo’ and ‘Hwasinbyeo’ were tested. They were planted onto MSagar medium (10 ml) in test tube (450 mm × φ30 mm) and incubated at 25oC and 28oC in growth chamberunder 12 hr light condition. Symptoms of over growth appeared a few days after seeding and then seedlingwere withered 2−3 weeks after over growth. The disease symptoms such as leaf dryness on top of rice wereappeared in the ‘Nampyeongbyeo’ from 28 days at the concentration of 105 spores/ml culturing at 28oC andthen withered completely 35 days after seeding. Whereas the other varieties withered entirely 19−23 daysafter seeding. Using the in vitro seedling screening method, 72 rice varieties were investigated to selectresistant cultivar. Finally, two resistant cultivars (‘Nampyeongbyeo’ and ‘Inwolbyeo’) and seven moderatelyresistant cultivars (‘Hwadongbyeo’, ‘Seokjeongbyeo’, ‘Samgwangbyeo’, ‘Sampyeongbyeo’, ‘Nonghobyeo’,‘Heukjinjubyeo’ and, ‘Joanbyeo’) were selected. If in vitro seedling screening method was used for evaluationof bakanae disease resistance, it would be completed within 35 days after sowing of rice seed.

Bakanae disease symptom were observed in barnyard grass in paddy field in Heanam, Jeonnam. The infected plants were blighted and white mass of spore were formed on the stem. Fusarium species were isolated from infected stem and the isolates were identified as Fusarium fujikuroi based on their morphological and molecular characteristics. The isolates of F. fujikuroi were assigned to reference of F. fujikuroi among related Fusarium species based on the translation elongation factor 1-alpha gene sequence. Pathogenicity of the fungal isolates was confirmed on seedlings of rice and barnyard grass by artificial inoculation. The results indicated that barnyard grass can be inoculum source of Bakanae disease on rice. Thus, effective weed management is necessary to Bakanae disease control and healthy seed production.

Soft rot caused by Rhizopus oryzae occurred on unshiu orange (Citrus unshiu Marc.) sampled from commercial markets in Jinju, Korea, 2010. The first symptom of soft rot on orange is a water-soaked appearance of the affected tissue. The infected parts later disintegrated into a mushy mass of disorganized cells followed by rapid softening of the diseased tissue. The lesion on orange was rapidly softened and rotted, then became brown or dark brown. Optimum temperature for mycelial growth of the causal fungus on potato dextrose agar was 30℃ and growth was still apparent at 37℃. Sporangiophores were 6~20 μm in diameter. Sporangia were globose and 40~200 μm in size. The color of sporangia was brownish-grey to blackish-grey at maturity. Sporangiospores were sub-globose, brownish- black streaked and 4~10 μm in size. Columella were globose to sub-globose and 85~120 μm in size. On the basis of mycological characteristics, pathogenicity test, and the ITS sequence analysis, the causal fungus was identified as Rhizopus oryzae. To our knowledge, this is the first report of soft rot caused by R. oryzae on unshiu orange in Korea.

Fucoidans are sulfated fucosylated polymers from the cell wall of brown algae. We assessed the effects of Fucus evanescens fucoidan on ultraviolet-B (UVB)-induced expression of matrix metalloproteinase-1 (MMP-1) protein, mRNA, and promoter, and the phosphorylation of mitogen-activated protein kinases in vitro using an immortalized human keratinocyte cell line. Pretreatment with 10 and 100 ㎍/ml fucoidan significantly inhibited UVB-induced MMP-1 protein, mRNA and promoter activity, compared to UVB irradiation alone. Extracellular signal regulated kinase activation was markedly inhibited by treatment with fucoidan, though c-JUN N-terminal kinase activity and p38 activation were only marginally affected by fucoidan. F. evanescens fucoidan may be a potential therapeutic agent for the prevention and treatment of skin photoaging.

During the period from 1999 to 2008, we surveyed the major diseases incidence of rice in Korea. Leaf blast showed 0.85% of the diseased leaf area in 2000 and then consistently decreased to 0.02% by 2008. However, panicle blast irregularly appeared by the years depending on weather conditions for disease development from heading to milk stage of rice. Diseased lesion height of sheath blight had the lowest (10.1%) incidence in 2001 and the highest (21.4%) incidence in 2007. A negative corelation ($r

Sclerotinia rot occurred sporadically on the stems and leaves of Astragalus sinicus in the farmers fields at Goseong-gun, Gyeongnam province in Korea. The infected plants showed the typical symptoms: watersoaked, wilt, rot, blight and eventual death. The colony of the isolated fungus on potato-dextrose agar (PDA) was white to faintly gray color. Sclerotia formed on the PDA were globose in shape, black in color and in size. The optimum temperature for mycelial growth and sclerotium formation was at on PDA. Apothecia formed on PDA were globose~disk in shape and 3~8 mm in size. Asci were cylindrical in shape and in size. Ascospores were ellipsoid and in size. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Sclerotinia trifoliorum Eriksson. This is the first report on sclerotinia rot of A. sinicus caused by Strifoliorum Eriksson in Korea.

We investigated the effect of the infection times and infection degrees at transplanting time of Zucchini yellow mosaic virus (ZYMV) on the growth and yield of cucumber plants at the semi-forcing and the retarding culture in 2007. When cucumber was inoculated with ZYMV at transplanting time, 15, 30, 45, 60, and 75 days after transplanting, vine length, internode length, number of leaf of the plants and marketable yield largely decreased as the cucumber infected earlier. The regression models were obtained between the disease incidence levels at 20 days after transplanting as the inoculation degrees and the marketable yield of cucumber: y

UVB reduces type I procollagen levels and increases matrix metalloproteinases-1 (MMP-1) levels in human skin and plays a major role in the process of photoaging. We previously reported that fucoidan inhibits UVB-induced MMP-1 expression at the protein and mRNA levels in human skin fibroblasts (HS68). Yet, the effects of fucoidan on UVB-induced MMP-1 promoter activity and type I procollagen have not been investigated. In this study, we assessed the effects of fucoidan on the inhibition of MMP-1 promoter activity and on the increase of type I procollagen synthesis in human skin fibroblasts. Fucoidan treatment significantly inhibited MMP-1 promoter activity compared to UVB irradiation alone. Fucoidan treatment also increased type I procollagen mRNA and protein expression in a dose-dependent manner compared to the control. Our data indicate that fucoidan may prevent UVB-induced MMP-1 expression and inhibit down-regulation of type I procollagen synthesis. We suggest that fucoidan may be a potential therapeutic agent to prevent and treat skin photoaging.

Recently organic farming practice of rice has been emerged in Korea, but one of the major limiting factor is the no effective environmental-friendly agro-materials to control major plant diseases. Bordeaux mixture has been used effectively as a preventive agro-chemical. The aim of this study was to investigate efficacy of Bordeanux mixture on control of rice blast caused by Magnaporthe grisea which is one of the disruptive rice diseases in world-wide. In greenhouse experiment, pre-treatment of 6-6 type of Bordeaux mixture before inoculation of spore suspension of M. grasea showed 71 % of control value. In field experiment, preventive applications of 4-8 and 6-6 types of Bordeaux mixture showed over 71 % of the control value. Chemical injury on rice leaves were not found in the application concentrations of all types of Bordeaux mixture, but observed in applications of Bordeaux mixtures between 30 and 100 diluted concentrations. This results indicate Bordeaux mixture can be used as an effective environmental-friendly agro-chemical to control rice blast disease in the field.

This experiment was conducted to find the causes of ineffective seed disinfection methods such as rice seeds soaking in hot water and prochloraz EC solution when the rice seeds were severely infected by Bakanae disease. In case of rice seeds collected from severely diseased field by Bakanae disease, the pathogen as the forms of spores and mycelium were infected in plumule and inner and outer integument of embryo, aleurone layer, and pericarp layer. When the rice seeds were soaked in hot water, the appearances of spores and hypha on the outer pericarp layer were severely disordered, however those of inner region of outer integument and aleurone layer were shown normal. The membrane of hypha on the outer pericarp layer was destroyed within 24 hours, while some spores were healthy and germinated 7 days after soaking, when the rice seeds soaked 24 hours in 125 ppm prochloraz solution at . These results indicated that the seed disinfection methods were ineffective on the Bakanae disease severely infected rice seed because the hot water did not transmit the pericarp layer of rice seed and also prochloraz solution did not effectively destroy the spore of pathogen.

For the eco-friendly control of fruit rot of fig, disease incidences according to the cultural practices at 51 fig orchards in south coast area of Korea were surveyed in 2002, and the effect of soil mulch and potassium phosphonate on fruit rot of fig was evaluated from 2002 to 2004. Diseased fruits of fig orchards of open field, rain shading, and vinyl house were 33.3%, 7.5%, and 0%, respectively. Diseased fruits were rated at 34.6%, 35.7%, and 27% as the tree spacing of , respectively. Among the soil mulching materials, barley straw showed disease incidence of 1.8% and 3.5% of diseased fruits compared to 42.1% and 48% of no mulching in 2002 and 2003, respectively. Diseased fruits in dark paper film mulching were recorded at 4.8% and 12% in 2002 and 2003, respectively, which were lower than those in dark polyethylene film mulching at 11.2% and 26.2%. When potassium phosphonate(1,000 ppm) was sprayed 3 times with 10 days intervals from the beginning of disease occurrence, disease incidences were rated at 3.0% and 2.0% in 2003 and 2004, respectively, which were much lower than those of control at 45.9 % and 39.3%.

To elucidate the potential impact of the variants of the UCP2 gene on obesity phenotypes, we have genotyped four polymorphisms in UCP2 among 988 Korean subjects using TaqMan ® methods, and three common haplotypes with frequency greater than 0.1 were constructed in the Korean population. No significant associations were detected with the risk of metabolic syndrome by logistic regression analyses. However, the 45 base-pair ins/del polymorphism (+3474 ins/del ) in the 3′ untranslated region (3′ UTR) showed significant association with body mass index ( P = 0.007, P corr = 0.02) and waist circumference ( P = 0.005). Further subgroup analysis revealed that the genetic effects were more apparent among female subjects. In addition, a summary of the controversial genetic effects on obesity mediated by UCP2 polymorphisms from previous studies is also given. Our results suggest that subjects with a 45 bp insertion allele of UCP2+ 3474 ins/del might have a higher risk of developing obesity, although the biological effects of this variant are not completely known.

This study was conducted to decide disease incidence level of rice leaf blast required for reasonable fungicide application in paddy field. We induced the disease development by inoculating rice blast pathogens on rice seedlings (Jinmibyeo) in the greenhouse and transplanting the infected seedlings in the field two weeks after rice plants were transplanted. We scored the disease incidence, grouped and marked according to degree of percentage of diseased leaf area at maximum stage of disease development. The percent diseased leaf area (PDLA) had negative correlations with panicle number per hill, ripened grain (%), and total yield; their correlation coefficients (r), , and , respectively. However, it had positive correlations with spikelets per panicle and thousand grain weight; their correlation coefficients (r), and , respectively. Gain threshold (GT) calculated based on control cost and market price was estimated to be 8.35. Economic injury level (EIL) obtained based on GT and coefficient of damage of regression equation between disease incidence and the different yield components; panicle number per hill, spikelets per panical, ripened grain(%), thousand grain weight and yield were 41.8, 9.7, 19.1, 291.1 and 3.4%, respectively. Economic threshold (ET) for yield was 2.7% () on PDLA. These results suggest that application of fungicide is necessary when two under leaves are almost covered with lesions or contained more than twenty large lesions under leaves at maximum tillering stage.

Summary Jasmonic acid (JA) plays pivotal roles in diverse plant biological processes, including wound response. Chloroplast lipid hydrolysis is a critical step for JA biosynthesis, but the mechanism of this process remains elusive. We report here that DONGLE ( DGL ), a homolog of DEFECTIVE IN ANTHER DEHISCENCE1 ( DAD1 ), encodes a chloroplast-targeted lipase with strong galactolipase and weak phospholipase A 1 activity. DGL is expressed in the leaves and has a specific role in maintaining basal JA content under normal conditions, and this expression regulates vegetative growth and is required for a rapid JA burst after wounding. During wounding, DGL and DAD1 have partially redundant functions for JA production, but they show different induction kinetics, indicating temporally separated roles: DGL plays a role in the early phase of JA production, and DAD1 plays a role in the late phase of JA production. Whereas DGL and DAD1 are necessary and sufficient for JA production, phospholipase D appears to modulate wound response by stimulating DGL and DAD1 expression.

SUMMARY Using cDNA microarray analysis, we isolated a cDNA clone, CaATL1 (Capsicum annuum L. Bukang AT-hook-Like gene 1), from a chili pepper plant incompatibly interacting with bacterial pathogens. The deduced amino acid sequence has a potential nuclear localization sequence and an AT-hook DNA binding motif which can bind AT-rich sequence elements. Expression of CaATL1 was specifically induced in host- and non-host-resistant responses against bacterial and viral pathogens in pepper plants. In addition, CaATL1 transcripts also increased following salicylic acid and ethephone treatment but were only mildly induced by methyl-jasmonate treatment. CaATL1::smGFP (soluble-modified green fluorescent protein) fusion protein localized to nuclei in tobacco BY2 protoplasts. The C-terminal region of the CaATL1 protein fused to the LexA DNA binding domain was able to activate reporter gene expression in yeast. To analyse further the role of the CaATL1 in pathogen defence response, we generated CaATL1-over-expressing transgenic tomato plants. These transgenic plants showed enhanced disease resistance against bacterial and oomycete pathogens. Taken together, these results provide the first evidence of a role for a plant AT-hook motif-containing transcription factor in pathogen defence response.

Agrobacterium tumefaciens-mediated transformation (ATMT) has become a prevalent tool for functional genomics of fungi, but our understanding of T-DNA integration into the fungal genome remains limited relative to that in plants. Using a model plant-pathogenic fungus, Magnaporthe oryzae, here we report the most comprehensive analysis of T-DNA integration events in fungi and the development of an informatics infrastructure, termed a T-DNA analysis platform (TAP). We identified a total of 1110 T-DNA-tagged locations (TTLs) and processed the resulting data via TAP. Analysis of the TTLs showed that T-DNA integration was biased among chromosomes and preferred the promoter region of genes. In addition, irregular patterns of T-DNA integration, such as chromosomal rearrangement and readthrough of plasmid vectors, were also observed, showing that T-DNA integration patterns into the fungal genome are as diverse as those of their plant counterparts. However, overall the observed junction structures between T-DNA borders and flanking genomic DNA sequences revealed that T-DNA integration into the fungal genome was more canonical than those observed in plants. Our results support the potential of ATMT as a tool for functional genomics of fungi and show that the TAP is an effective informatics platform for handling data from large-scale insertional mutagenesis.

To understand the molecular basis of a phosphoryl transfer reaction catalyzed by the 6-phosphofructo-2-kinase domain of the hypoxia-inducible bifunctional enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB3), the crystal structures of PFKFB3AMPPCPfructose-6-phosphate and PFKFB3ADPphosphoenolpyruvate complexes were determined to 2.7 A and 2.25 A resolution, respectively. Kinetic studies on the wild-type and site-directed mutant proteins were carried out to confirm the structural observations. The experimentally varied liganding states in the active pocket cause no significant conformational changes. In the pseudo-substrate complex, a strong direct interaction between AMPPCP and fructose-6-phosphate (Fru-6-P) is found. By virtue of this direct substrate-substrate interaction, Fru-6-P is aligned with AMPPCP in an orientation and proximity most suitable for a direct transfer of the gamma-phosphate moiety to 2-OH of Fru-6-P. The three key atoms involved in the phosphoryl transfer, the beta,gamma-phosphate bridge oxygen atom, the gamma-phosphorus atom, and the 2-OH group are positioned in a single line, suggesting a direct phosphoryl transfer without formation of a phosphoenzyme intermediate. In addition, the distance between 2-OH and gamma-phosphorus allows the gamma-phosphate oxygen atoms to serve as a general base catalyst to induce an "associative" phosphoryl transfer mechanism. The site-directed mutant study and inhibition kinetics suggest that this reaction will be catalyzed most efficiently by the protein when the substrates bind to the active pocket in an ordered manner in which ATP binds first.

Plants constantly monitor environmental fluctuations to optimize their growth and metabolism. One example is adaptive growth occurring in response to biotic and abiotic stresses. Here, we demonstrate that GH3-mediated auxin homeostasis is an essential constituent of the complex network of auxin actions that regulates stress adaptation responses in Arabidopsis. Endogenous auxin pool is regulated, at least in part, through negative feedback by a group of auxin-inducible GH3 genes encoding auxin-conjugating enzymes. An Arabidopsis mutant, wes1-D, in which a GH3 gene WES1 is activated by nearby insertion of the (35)S enhancer, exhibited auxin-deficient traits, including reduced growth and altered leaf shape. Interestingly, WES1 is also induced by various stress conditions as well as by salicylic acid and abscisic acid. Accordingly, wes1-D was resistant to both biotic and abiotic stresses, and stress-responsive genes, such as pathogenesis-related genes and CBF genes, were upregulated in this mutant. In contrast, a T-DNA insertional mutant showed reduced stress resistance. We therefore propose that GH3-mediated growth suppression directs reallocation of metabolic resources to resistance establishment and represents the fitness costs of induced resistance.

Collectotrichum acutatum is a fungal plant pathogen that causes pre- and post-harvest anthracnose on a wide range of plants worldwide. The complete mitochondrial genome of C. acutatum has been determined for the first time. This study revealed that the mitogenome of C. acutatum is a closed circular molecule of 30 892 bp in length, with a G + C content of 34.7%, which include 15 protein-coding genes, 22 tRNA genes, and two rRNA genes. All the protein-coding genes, accounting for 46.6% of the C. acutatum mitogenome, start with the standard ATG codon and end with the TAA termination codon except for nad6 gene using the TAG termination codon. The mitogenome information of C. acutatum can provide molecular basis for further studies on molecular systematics and evolutionary dynamics.

This study examined the effect of amyloid beta peptide (Abeta) and the secretase inhibitors of amyloid precursor proteins (APP) on the spontaneous apoptosis of neutrophils. Abeta(1-40) decreased the apoptotic rate of neutrophils. The delayed apoptosis by Abeta was not blocked by pertussis toxin and N-formyl peptide receptor-like 1 antagonistic peptide, WRWWWW. The inhibitors of phoshoinositide 3-kinase (LY294002), phospholipase C (U73122), or Ca++-dependent protein kinase C (Go6976) abrogated the anti-apoptotic effect of Abeta on neutrophils. Moreover, the Abeta-induced delay of apoptosis was inhibited by a calcium chelator, BAPTA/AM. The amount of the APP protein was reduced in the cultured neutrophils and the APP level in the Abeta or pancaspase-treated neutrophils was lower than that in the cultured neutrophils. However, the reduction in APP level was recovered after treating them with the secretase inhibitors or anti-Fas antibody. The exogenous addition of cell permeable beta- and gamma-secretase inhibitors resulted in an increase in the rate of the apoptosis. The regulation of neutrophil apoptosis by the addition of Abeta and secretase inhibitors occurred via the caspase -8, -9, -3, and mitochondrial-dependent pathways. This suggests that the intracellular beta-amyloid proteins play a role as regulating factor of neutrophil survival and that Abeta-induced delay of apoptosis is mediated by other receptors rather than a seven-transmembrane G protein-coupled receptor(s).

The structure of the type I tetraheme cytochrome c 3 from Desulfovibrio desulfuricans G20 was determined to 1.5 A by X-ray crystallography. In addition to the oxidized form, the structure of the molybdate-bound form of the protein was determined from oxidized crystals soaked in sodium molybdate. Only small structural shifts were obtained with metal binding, consistent with the remarkable structural stability of this protein. In vitro experiments with pure cytochrome showed that molybdate could oxidize the reduced cytochrome, although not as rapidly as U(VI) present as uranyl acetate. Alterations in the overall conformation and thermostability of the metal-oxidized protein were investigated by circular dichroism studies. Again, only small changes in protein structure were documented. The location of the molybdate ion near heme IV in the crystal structure suggested heme IV as the site of electron exit from the reduced cytochrome and implicated Lys14 and Lys56 in binding. Analysis of structurally conserved water molecules in type I cytochrome c 3 crystal structures identified interactions predicted to be important for protein stability and possibly for intramolecular electron transfer among heme molecules.

The hypoxia-inducible form of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB3) plays a crucial role in the progression of cancerous cells by enabling their glycolytic pathways even under severe hypoxic conditions. To understand its structural architecture and to provide a molecular scaffold for the design of new cancer therapeutics, the crystal structure of the human form was determined. The structure at 2.1 A resolution shows that the overall folding and functional dimerization are very similar to those of the liver (PFKFB1) and testis (PFKFB4) forms, as expected from sequence homology. However, in this structure, the N-terminal regulatory domain is revealed for the first time among the PFKFB isoforms. With a β-hairpin structure, the N terminus interacts with the 2-Pase domain to secure binding of fructose-6-phosphate to the active pocket, slowing down the release of fructose-6-phosphate from the phosphoenzyme intermediate product complex. The C-terminal regulatory domain is mostly disordered, leaving the active pocket of the fructose-2,6-bisphosphatase domain wide open. The active pocket of the 6-phosphofructo-2-kinase domain has a more rigid conformation, allowing independent bindings of substrates, fructose-6-phosphate and ATP, with higher affinities than other isoforms. Intriguingly, the structure shows an EDTA molecule bound to the fructose-6-phosphate site of the 6-phosphofructo-2-kinase active pocket despite its unfavorable liganding concentration, suggesting a high affinity. EDTA is not removable from the site with fructose-6-P alone but is with both ATP and fructose-6-P or with fructose-2,6-bisphosphate. This finding suggests that a molecule in which EDTA is covalently linked to ADP is a good starting molecule for the development of new cancer-therapeutic molecules.

Fungal hydrophobins are implicated in cell morphogenesis and pathogenicity in several plant pathogenic fungi including the rice blast fungus Magnaporthe grisea. A cDNA clone encoding a hydrophobin (magnaporin, MHP1) was isolated from a cDNA library constructed from rice leaves infected by M. grisea. The MHP1 codes for a typical fungal hydrophobin of 102 amino acids containing eight cysteine residues spaced in a conserved pattern. Hydropathy analysis of amino acids revealed that MHP1 belongs to the class II group of hydrophobins. The amino acid sequence of MHP1 exhibited about 20% similarity to MPG1, an M. grisea class I hydrophobin. Expression of MHP1 was highly induced during plant colonization and conidiation, but could hardly be detected during mycelial growth. Transformants in which MHP1 was inactivated by targeted gene replacement showed a detergent wettable phenotype, but were not altered in wettability with water. mhp1 mutants also exhibited pleiotropic effects on fungal morphogenesis, including reduction in conidiation, conidial germination, appressorium development and infectious growth in host cells. Furthermore, conidia of mhp1 mutants were defective in their cellular organelles and rapidly lose viability. As a result, mhp1 mutants exhibited a reduced ability to infect and colonize a susceptible rice cultivar. These phenotypes were recovered by re-introduction of an intact copy of MHP1. Taken together, these results indicate that MHP1 has essential roles in surface hydrophobicity and infection-related fungal development, and is required for pathogenicity of M. grisea.

We have isolated a cDNA clone for the antifungal protein,CaAFP, from hot pepper,Capsicum annuum L. Its open reading frame encodes 85 amino acids, including 8 cysteine residues. CaAFP consists of three domains: a signal peptide, a chitin-binding domain, and a C-terminal peptide domain. The deduced amino acid sequence of the chitin-binding domain shows 92% and 85% similarity to the same domain from PnAMPs and hevein, respectively. Southern blot analysis indicated that CaAFP is present as a single copy, while the northern blots revealed that the clone is highly expressed in the leaves and flower buds, but not in the roots. However, wounding treatments and chemicals generally known to induce PR proteins did not stimulate its expression.In situ hybridization also showed that CaAFP is expressed in the parenchyma cells of the floral sepals. As seen in our functional analysis, this clone was expressed inEscherichia coli, and the fusion protein was purified using nickel-affinity column chromatography. This purified AFP fusion protein inhibited spore germination and appressoria formation in several plant pathogenic fungi, includingFusarium oxisporum andColletotrichum gloeosporioides. Our results suggest CaAFP is an antifungal protein that defends developing seeds against pathogen invasion while also having a specific biological role during floral development.

To make the forecasting model of rice bacterial grain rot (RGBR) using the statistical procedures with SAS(Statistical Analysis System) based on micro-weather factors during heading period of rice, 21 rice varieties having the different heading time (40％ panicles headed) were planted at 30 May and 15 June in Naju. Heading time and diseased panicles were investigated from July to August in 1998. RGBR mainly occurred on varieties headed from 29 July to 19 August, but not on varieties headed after 22 August. RGBR was highly correlated with diurnal temperature during 7 days (r