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Northern corn leaf blight caused by Setosphaeria turcicais one of the most important fungal diseases of maize. We previously cloned and analyzed the gene encoding protein kinase C (PKC) in S. turcica, as this Ca2+signaling component is required for growth and pathogenicity of several other plant pathogenic fungi. Here, we assessed the effect of PKCknockout on S. turcicapathogenicity using four quinic-acid-inducible PKCantisense mutants. The conditional mutants enabled us to study the role of PKCin growth, germination, appressorium development, and pathogenicity despite the fact that constitutive PKCknockout is typically lethal in filamentous fungi. The growth rates of the mutants were the same as that of the wild type (WT) on PDA medium but were much lower on PDA medium that contained the inducer 15 mM quinic acid. Conidial germination and appressorium development were almost completely abolished in the induced mutants, and penetration experiments showed that appressoria from the WT could penetrate cellophane, whereas those of the induced mutants could not. Inoculation experiments showed that the mutant strains failed to produce visible lesions on unwounded maize leaves, although they were able to infect wounded leaves, suggesting that they were impaired in the process of host penetration. Characterization of PKCantisense mutants thus highlighted multiple roles of PKC in S. turcicapathogenicity, laying a foundation for understanding and exploiting a key signal transduction pathway in plant pathogenic fungi.

Molybdenum doping is an effective way to improve the oxygen evolution reaction(OER) properties of catalysts, which can efficiently improve the electronic conductivity, mass transport process, and intrinsic activity of transition metal oxides or hydroxides, especially for those multi-component oxides with more abundant active sites. Herein, we have prepared a quaternary FeCoMoCu metal oxide on Cu foam(FeCoMoCuOx@Cu) as an efficient OER catalyst. As expected, FeCoMoCuOx@Cu could exhibit a low overpotential(252 mV at the current density of 10 mA/cm2) and exceptional stability(10000 cycles of CV scans or constant electrolysis for 48 h).

AbstractAs a valuable and powerful platform technology, yeast surface display (YSD) has been widely used in various biotechnological fields, but little in agricultural applications. Xylanase can be used as an elicitor in the plant–pathogen interaction system and induce corn defence response. In this study, the YSD technology was used to express the xylanase protein family from Setosphaeria turcica, which is a novel strategy for plant protection. First, five genes encoding xylanase were selected from the S. turcicagenome database. The conserved domains of these genes were analyzed, which revealed that these genes were highly conserved. Here, we selected two of the five genes and expressed them by a prokaryotic expression system, but the two xylanase genes were expressed in inclusion bodies and showed no activity. To make them available in the application, we successfully constructed them in a YSD system. The products were detected for enzyme activities and the activities of two xylanases were 16.72 and 19.12 U/mL, respectively. We finally proved that the yeast-displaying xylanase was an efficient strategy to induce corn defence response, as four defence genes in corn, PR-1, PR-4, SODand CATwere induced after treatment with the yeast displaying xylanases.

Particulate matter (PM) pollution is a serious threat to human health. Zeolitic imidazolate framework-8 (ZIF-8) is a kind of metal-organic framework, and ZIF-8 not only can capture PM2.5efficiently but also possesses excellent chemical and thermal stability. In this study, ZIF-8-modified soluble polyimide (PI) nanofibrous membranes were prepared via an electrospinning process. As a result, the PI-ZIF membrane shows high PM2.5filtration efficiency (up to 96.6 ± 2.9%), superior thermal stability (up to 300 °C), good transmittance, excellent mechanical properties, and low pressure drop. The prepared PI-ZIF membrane with excellent comprehensive property shows a promising application in PM2.5capture, especially in harsh conditions.

ABSTRACTHeterotrimeric G proteins are best known for their role in the transduction of extracellular signals to various downstream effectors. G proteins in higher eukaryotes are intensively studied; however, their roles in foliar pathogens are still elusive. In this study, we cloned the gene Stgg1encoding G protein γ subunit in Setosphaeria turcicaand investigated its function by RNA interference technology. Three independent Stgg1targeted RNAi mutants R3, R5 and R6 with diverse silencing efficiency were generated. Knock-down of Stgg1resulted in a significant reduction in mRNA levels of the genes encoding Gα (Stga1, Stga2, Stga3) but not for Gβ (Stgb1). Stgg1RNAi mutants exhibited significantly elongated hyphal cells with blocked conidium production. In addition, Stgg1RNAi mutants all appeared in lighter colony colour compatible with inhibited secondary metabolites. Further assays demonstrated that Stgg1was required for biosynthesis of melanin and HT-toxin activity. Furthermore, down-regulation of Stgg1largely inhibited the inflection capacity. Thus, we proposed that Stgg1played crucial roles in conidiation, secondary metabolite production and pathogenicity of S. turcicaand is, therefore, an ideal target for drug design against foliar pathogens.

Septins are a conserved group of GTP-binding proteins found in all eukaryotes and are the fourth-most abundant cytoskeletal proteins. Septins of some pathogenic fungi are involved in morphological changes related to infection. Our previous studies have identified four core septins (StSep1-4) in Setosphaeria turcica, the causal agent of northern corn leaf blight, while only StSep4is significantly upregulated during the invasive process. We therefore used forchlorfenuron (FCF), the specific inhibitor of septin, and ΔStSep4knockout mutants to further clarify the role of septins in S. turcicapathogenicity. FCF treatment caused a dose-dependent reduction in S. turcicacolony growth, delayed the formation of infection structures, and reduced the penetration ability. ΔStSep4knockout mutants displayed abnormal mycelium morphology, slow mycelial growth, conidiation deficiency, delayed appressorium development, and weakened pathogenicity. StSep4deletion also broke cell wall integrity, altered chitin distribution, decreased the melanin content, and disrupted normal nuclear localization. A transcriptomic comparison revealed that genes differentially expressed between ΔStSep4and WT were enriched in terms of ribosomes, protein translation, membrane components, and transmembrane transport activities. Our results demonstrate that StSep4is required for morphology and pathogenicity in S. turcica, making it a promising target for the development of novel fungicides.

In order to clarify the roles of different protein kinase A (PKA) isoforms during the pathogenesis, a gene coding the catalytic subunit of PKA (PKA-c) of S. turcicawas predicted from the genome database. In addition, the transcriptional profile during the formation of the invasive structure was studied through qPCR. Results showed that the StpkaC2gene harbored an ORF of 1209 bp that encoded the PKA-c with its 402 amino acid residues. Phylogenetic analysis revealed that StpkaC2and StpkaC1belonged to different clusters. Gene expression patterns of StpkaC2during germ tube formation was 2.2 times higher than that at the conidial phase (control), but decreased slightly during appressoria formation and mature stages of infection. During the intrusive filament formation stage, gene expression increased to levels that were 4.2 times higher than the control. Instead, the mRNA levels of StpkaC1were similar at 0, 3, 6 and 12 hpi. However, at 24 hpi, gene expression increased to levels that were 3.2 times higher than that control. Results suggest that StpkaC2is more active than StpkaC1during germ tube and appressoria formation, and mature stages. Conversely, both StpkaC2and StpkaC1are important during the invasive hyphae formation stage.

The latent pigment 1,4-dioxo-2,5-di-tert-butoxycarbonyl-3,6-diphenyl-1,2,4,5-tetrahydropyrrolo[3,4-c]pyrrole (abbreviated DPP-Boc) has been found to exist in the solid state in two polymorphic forms, denoted the α and β phases. Above ambient temperature, a thermal decomposition reaction occurs in both polymorphs to produce the commercially important pigment DPP. Significant differences have been observed in kinetic aspects of this reaction in the α and β phases, and such differences in reactivity must ultimately originate from structural differences between the two polymorphs. In this paper we focus on establishing a structural understanding of these materials. The structure of the α phase of DPP-Boc has been determined previously from single crystal X-ray diffraction data, although certain features of the reported structure are unsatisfactory. Here we report a revised structure determination of the α phase by Rietveld refinement from powder X-ray diffraction data. The structure of the β phase of DPP-Boc, which was previously unknown, has been solved directly from powder X-ray diffraction data using our Monte Carlo technique and Rietveld refinement. A detailed description and comparison of the structural properties of the α and β phases of DPP-Boc is presented.

Rhabdomyosarcoma arising in abdomen and pelvis is an uncommon but important type of soft tissue sarcoma, posing a great challenge for clinicians. Sporadic cases of intra-abdominal rhabdomyosarcoma were reported, but mostly in pediatrics. We demonstrated a rare case of primary abdominopelvic rhabdomyosarcoma in an elderly woman who presented with a notable increase in abdominal circumference and constipation. Abdominal magnetic resonance imaging showed a huge mass throughout the abdomen and pelvis. Cytoreductive surgery was performed by gynecologists due to the suspicious diagnosis of disseminated leiomyosarcoma. However, the final pathological analysis revealed embryonal rhabdomyosarcoma. Although adjuvant chemotherapy was administered, localized recurrence was identified 6 months after the initial operation. Gynecologists and radiologists should be aware of it so it can be listed in the differential diagnosis of masses that primarily arise in the abdomen and pelvis.