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The identification effector targets and characterization of their functions are crucial for understanding pathogen infection mechanisms and components of plant immunity. Here, we identify the effector UgsL, a ustilaginoidin synthetase with a key role in regulating virulence of the rice false smut fungus Ustilaginoidea virens. Heterologous expression of UgsL in rice (Oryza sativa) enhances plant susceptibility to multiple pathogens, and host-induced gene silencing of UgsL enhances plant resistance to U. virens, indicating that UgsL inhibits rice immunity. UgsL interacts with STRUBBELIG RECEPTOR KINASE 3 (OsSRF3). Genome editing and overexpression of OsSRF3 demonstrate that OsSRF3 plays a pivotal role in the resistance of rice to multiple pathogens. Remarkably, overexpressing OsSRF3 enhances resistance without adversely affecting plant growth or yield. We show that BRASSINOSTEROID RECEPTOR-ASSOCIATED KINASE 1 (OsBAK1) interacts with and phosphorylates OsSRF3 to activate pathogen-triggered immunity, inducing the mitogen-activated protein kinase cascade, a reactive oxygen species burst, callose deposition, and expression of defense-related genes. UgsL interferes with the phosphorylation of OsSRF3 by OsBAK1. Furthermore, UgsL mediates OsSRF3 degradation by facilitating its association with the ubiquitin-26S proteasome. Our results reveal that OsSRF3 positively regulates immunity in rice and that UgsL mediates its degradation, thereby inhibiting the activation of OsBAK1–OsSRF3-mediated immune pathways. The Ustilaginoidea virens effector UgsL is shown to interact with receptor kinase OsSRF3. OsSRF3 positively regulates immunity in rice and UgsL mediates its degradation, thereby inhibiting the activation of OsBAK1–OsSRF3-mediated immune responses in rice. [ABSTRACT FROM AUTHOR]

Summary: Rice false smut caused by Ustilaginoidea virens is a devastating rice (Oryza sativa) disease worldwide. However, the molecular mechanisms underlying U. virens–rice interactions are largely unknown. In this study, we identified a secreted protein, Uv1809, as a key virulence factor. Heterologous expression of Uv1809 in rice enhanced susceptibility to rice false smut and bacterial blight. Host‐induced gene silencing of Uv1809 in rice enhanced resistance to U. virens, suggesting that Uv1809 inhibits rice immunity and promotes infection by U. virens. Uv1809 suppresses rice immunity by targeting and enhancing rice histone deacetylase OsSRT2‐mediated histone deacetylation, thereby reducing H4K5ac and H4K8ac levels and interfering with the transcriptional activation of defence genes. CRISPR‐Cas9 edited ossrt2 mutants showed no adverse effects in terms of growth and yield but displayed broad‐spectrum resistance to rice pathogens, revealing a potentially valuable genetic resource for breeding disease resistance. Our study provides insight into defence mechanisms against plant pathogens that inactivate plant immunity at the epigenetic level. [ABSTRACT FROM AUTHOR]

As the performance requirements of insulated gate bipolar transistors (IGBTs) in various fields of power electronic systems are increasing, the IGBT power module package structure, aging mechanism analysis, and selection of health state characteristic parameters are of great significance to ensure the normal operation of power systems. At present, research on the aging failure of welded IGBT modules is relatively comprehensive and can be divided into chip aging failure and package aging failure according to their failure parts. However, there is some research on the relationship between aging failure and the characteristic quantity of power modules, but no definite system has been formed. Therefore, in this paper, the packaging structure of the solder-type IGBT modules and the aging mechanism caused by different aging reasons were summarized. Moreover, the health status monitoring of solder-type IGBT modules from the junction temperature, bonding line, solder layer, and package insulation aging health status monitoring and its quantitative assessment research progress was analyzed in detail. Also, the health state evaluation index system of the solder-type IGBT modules was completed on the basis of voltage, current, thermal, insulation parameters, and other characteristic quantities. Finally, based on the analysis of domestic and international research problems, the development trend and direction of the condition monitoring technology of solder-type IGBT modules is foreseen. The research on condition monitoring for welded IGBT module technology has a certain significance. [ABSTRACT FROM AUTHOR]

Based on the alkali resistance of polyester/TGIC, polyester/HAA, polyester/epoxy and polyurethane powder coatings, the hydroxy-terminated polyester resin is modified by means of using some monomer containing steric groups and improving the crosslinking density. The results show that polyester/TGIC and polyester/HAA systems have the worst alkali resistance, polyester/epoxy system is slightly better, and polyurethane system is the best. The modified hydroxy-terminated polyester resin has good mechanical properties, adhesion, boiling water resistance and excellent alkali resistance. At 30 °C, soaked by 50%wt NaOH for 96 h, the gloss retention rate is 77% with no cracking and other defects. At 60 °C, soaked by 50%wt NaOH for 22 h, the gloss retention rate is 60% with no cracking and other defects. [ABSTRACT FROM AUTHOR]

Rice ARGONAUTE2 (OsAGO2) is a core component of the rice RNA‐induced silencing complex (RISC), which is repressed by Magnaporthe oryzae (M. oryzae) infection. Whether and how OsAGO2‐mediated gene silencing plays a role in rice blast resistance and which sRNAs participate in this process are unknown. Our results indicate that OsAGO2 is a key immune player that manipulates rice defense responses against blast disease. OsAGO2 associates with the 24‐nt miR1875 and binds to the promoter region of HEXOKINASE1 (OsHXK1), which causes DNA methylation and leads to gene silencing. Our multiple genetic evidence showed that, without M. oryzae infection, OsAGO2/miR1875 RISC promoted OsHXK1 promoter DNA methylation and OsHXK1 silencing; after M. oryzae infection, the reduced OsAGO2/miR1875 led to a relatively activated OsHXK1 expression. OsHXK1 acts as a positive regulator of blast disease resistance that OsHXK1‐OE rice exhibited enhanced resistance, whereas Cas9‐Oshxk1 rice showed reduced resistance against M. oryzae infection. OsHXK1 may function through its sugar sensor activity as glucose induced defense‐related gene expression and reactive oxygen species (ROS) accumulation in Nipponbare and OsHXK1‐OE but not in Cas9‐Oshxk1 rice. OsAGO2 itself is delicately regulated by OsPRMT5, which senses M. oryzae infection and attenuates OsAGO2‐mediated gene silencing through OsAGO2 arginine methylation. Our study reveals an OsPRMT5‐OsAGO2/miR1875‐OsHXK1 regulatory module that fine tunes the rice defense response to blast disease. [ABSTRACT FROM AUTHOR]

This article explores the relationship between the fungus Ustilaginoidea virens and the WRKY transcription factor OsWRKY31 in rice plants. The researchers discovered that a specific protein, UvSec117, is a key factor in the virulence of U. virens and interacts with OsWRKY31. They also found that OsWRKY31 positively regulates rice's resistance to various diseases. Through further experiments, they identified the target genes of OsWRKY31, which are involved in induced systemic resistance and the salicylic acid/jasmonic acid signaling pathways. This research provides valuable insights into the molecular mechanisms of rice's resistance to grain-infecting pathogens and has implications for breeding disease-resistant rice varieties. [Extracted from the article]

Saccharomyces cerevisiae is a eukaryotic organism with a clear genetic background and mature gene operating system; in addition, it exhibits environmental tolerance. Therefore, S. cerevisiae is one of the most commonly used organisms for the synthesis of biological chemicals. The investigation of fatty acid catabolism in S. cerevisiae is crucial for the synthesis and accumulation of fatty acids and their derivatives, with β-oxidation being the predominant pathway responsible for fatty acid metabolism in this organism, occurring primarily within peroxisomes. The latest research has revealed distinct variations in β-oxidation among different fatty acids, primarily attributed to substrate preferences and disparities in the metabolic regulation of key enzymes involved in the S. cerevisiae fatty acid metabolic pathway. The synthesis of lipids, on the other hand, represents another crucial metabolic pathway for fatty acids. The present paper provides a comprehensive review of recent research on the key factors influencing the efficiency of fatty acid utilization, encompassing β-oxidation and lipid synthesis pathways. Additionally, we discuss various approaches for modifying β-oxidation to enhance the synthesis of fatty acids and their derivatives in S. cerevisiae , aiming to offer theoretical support and serve as a valuable reference for future studies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wang, Su, Zhang, Shangguan, Wang and Su.)