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BackgroundDuring the disease cycle, plant pathogenic fungi exhibit a morphological transition between hyphal growth (the phase of active infection) and the production of long-term survival structures that remain dormant during "overwintering." Verticillium dahliae is a major plant pathogen that produces heavily melanized microsclerotia (MS) that survive in the soil for 14 or more years. These MS are multicellular structures produced during the necrotrophic phase of the disease cycle. Polyketide synthases (PKSs) are responsible for catalyzing production of many secondary metabolites including melanin. While MS contribute to long-term survival, hyphal growth is key for infection and virulence, but the signaling mechanisms by which the pathogen maintains hyphal growth are unclear.ResultsWe analyzed the VdPKSs that contain at least one conserved domain potentially involved in secondary metabolism (SM), and screened the effect of VdPKS deletions in the virulent strain AT13. Among the five VdPKSs whose deletion affected virulence on cotton, we found that VdPKS9 acted epistatically to the VdPKS1-associated melanin pathway to promote hyphal growth. The decreased hyphal growth in VdPKS9 mutants was accompanied by the up-regulation of melanin biosynthesis and MS formation. Overexpression of VdPKS9 transformed melanized hyphal-type (MH-type) into the albinistic hyaline hyphal-type (AH-type), and VdPKS9 was upregulated in the AH-type population, which also exhibited higher virulence than the MH-type.ConclusionsWe show that VdPKS9 is a powerful negative regulator of both melanin biosynthesis and MS formation in V. dahliae. These findings provide insight into the mechanism of how plant pathogens promote their virulence by the maintenance of vegetative hyphal growth during infection and colonization of plant hosts, and may provide novel targets for the control of melanin-producing filamentous fungi.

The large length of silicon nanowires (SiNWs) leads to their good optical properties, which causes increasing losses in the electrical performance of solar cells. The SiNWs in PEDOT:PSS/Si hybrid solar cells were optimized by simulations and experiments, and the effects of surface recombination rate and series resistance caused by SiNWs length on the performance of solar cells were studied. The results show that with the increase of SiNWs length, the surface recombination mainly affects the open circuit voltage and has great influence on the performance of solar cells. Moreover, the series resistance mainly affects the filling factor and has little effect on the performance of solar cells. Experiments show that when the length of SiNWs is about 246 nm, the highest conversion efficiency (12.88%) of PEDOT:PSS/Si hybrid solar cells can be obtained. The research results can provide guidance for the design of Si-based solar cells with SiNWs.

Verticillium dahliae is a destructive soil-borne pathogen of many economically important dicots. The genetics of pathogenesis in V. dahliae has been extensively studied. Spt-Ada-Gcn5 acetyltransferase complex (SAGA) is an ATP-independent multifunctional chromatin remodeling complex that contributes to diverse transcriptional regulatory functions. As members of the core module in the SAGA complex in Saccharomyces cerevisiae, Ada1, together with Spt7 and Spt20, play an important role in maintaining the integrity of the complex. In this study, we identified homologs of the SAGA complex in V. dahliae and found that deletion of the Ada1 subunit (VdAda1) causes severe defects in the formation of conidia and microsclerotia, and in melanin biosynthesis and virulence. The effect of VdAda1 on histone acetylation in V. dahliae was confirmed by western blot analysis. The deletion of VdAda1 resulted in genome-wide alteration of the V. dahliae transcriptome, including genes encoding transcription factors and secreted proteins, suggesting its prominent role in the regulation of transcription and virulence. Overall, we demonstrated that VdAda1, a member of the SAGA complex, modulates multiple physiological processes by regulating global gene expression that impinge on virulence and survival in V. dahliae.

Mounting evidence demonstrates that hydrogen sulfide (H2S) promotes anti-inflammatory molecules and inhibits pro-inflammatory cytokines in endothelial cells (ECs). This study aims to investigate the favorable action of H2S on endothelial function in senescence by inhibiting the production of inflammatory molecules. Senescent ECs exhibit a reduction in H 2S, endothelial nitric oxide synthase (eNOS) and peroxisome proliferator-activated receptor δ (PPARδ), coupled with increased inflammatory molecules, sodium glucose transporter type 2 (SGLT2) and phosphorylation of STAT3, which could be reversed by the administration of a slow but sustained release agent of H2S, GYY4137. Decreased production of eNOS and upregulated p-STAT3 and SGLT2 levels in senescent ECs are reversed by replenishment of the SGLT2 inhibitor EMPA and the PPARδ agonist GW501516. The PPARδ antagonist GSK0660 attenuates eNOS expression and increases the production of p-STAT3 and SGLT2. However, supplementation with GYY4137 has no beneficial effect on GSK0660-treated ECs. GYY4137, GW501516 and EMPA preserve endothelial-dependent relaxation (EDR) in D-gal-treated aortae, while GSK0660 destroys aortic relaxation even with GYY4137 supplementation. In summary, senescent ECs manifest aggravated the expressions of the inflammatory molecules SGLT2 and p-STAT3 and decreased the productions of PPARδ, eNOS and CSE. H2S ameliorates endothelial dysfunction through the anti-inflammatory effect of the PPARδ/SGLT2/p-STAT3 signaling pathway in senescent ECs and may be a potential therapeutic target for anti-ageing treatment.

The efficient and comprehensive utilization of solar energy is of great significance for the sustainable development of energy and the realization of the strategic objectives of peak carbon dioxide emissions and carbon neutralization. Firstly, focus on the two main solar energy utilization modes, photovoltaic and photothermal, we systematically introduced the main types, research status and development trend of photovoltaic technologies, as well as the current situation and development trend of thermal power generation, building heating and refrigeration, seawater desalination and industrial heating in photothermal utilization. Then, we discussed the basic principles, main types and research progress of photovoltaic/thermal integration technology, especially the integration technology combined with the phase change heat transfer mode, was systematically introduced. Finally, several flexible "photovoltaic +" solar energy utilization technologies were introduced briefly. Photovoltaic, photothermal, photovoltaic/thermal integration and "photovoltaic +" technologies are still in a period of rapid development, have huge application potential and breed a large number of new technological growth points. These technologies are of great significance to solve the energy and environmental crisis and maintain the sustainable development of human society.

The remarkable efficacy of COVID-19 vaccines has established mRNA as a highly promising biomedical technology. However, the adequate application of mRNA therapeutics necessitates additional measures to mitigate the inherent immunogenicity, which is predominantly caused by dsRNA. As a byproduct of the in vitro transcription of mRNA, dsRNA was reported to be originated through several distinct mechanisms, including the extension of 3′ loop-back hairpins, the extension of hybridized abortive transcripts, and promoter-independent transcription. The intricate mechanisms involved pose a dilemma as the reduction in dsRNA results in a concomitant decrease in other critical quality attributes of mRNA. Here, we demonstrate that the promoter binding motifs of T7 RNA polymerase directly impact the production of promoter-independent transcription-based dsRNA. Specifically, the G753A mutation significantly reduces the formation of dsRNA byproducts, which can further combine with modified nucleotides to enhance the effectiveness of dsRNA mitigation and with previously reported high-integrity mutation K389A to minimize side effects. Accordingly, the present study reports a cost-effective approach to synthesize high-purity, less immunostimulatory mRNA by using an engineered T7 RNA polymerase mutant. [ABSTRACT FROM AUTHOR]

Objective: To explore the effect of CO2 laser combined with low-temperature plasma radiofrequency ablation on the early glottic laryngeal carcinoma. Methods: 70 patients with early glottic laryngeal carcinoma were enrolled in this retrospective study. The patients (40 cases) in the control group were treated by CO2 laser. The patients in the combination group (30 cases) were treated by CO2 laser combined with low-temperature plasma radiofrequency ablation. Results: The postoperative recurrence rate in the combination group was notably decreased than the control group (P