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As a signaling molecule, nitric oxide (NO) regulates the development and stress response in different organisms. The major biological activity of NO is protein S‐nitrosylation, whose function in fungi remains largely unclear. Here, it is found in the rice blast fungus Magnaporthe oryzae, de‐nitrosylation process is essential for functional appressorium formation during infection. Nitrosative stress caused by excessive accumulation of NO is harmful for fungal infection. While the S‐nitrosoglutathione reductase GSNOR‐mediated de‐nitrosylation removes excess NO toxicity during appressorium formation to promote infection. Through an indoTMT switch labeling proteomics technique, 741 S‐nitrosylation sites in 483 proteins are identified. Key appressorial proteins, such as Mgb1, MagB, Sps1, Cdc42, and septins, are activated by GSNOR through de‐nitrosylation. Removing S‐nitrosylation sites of above proteins is essential for proper protein structure and appressorial function. Therefore, GSNOR‐mediated de‐nitrosylation is an essential regulator for appressorium formation. It is also shown that breaking NO homeostasis by NO donors, NO scavengers, as well as chemical inhibitor of GSNOR, shall be effective methods for fungal disease control. [ABSTRACT FROM AUTHOR]

Summary: Plant pathogenic fungi elaborate numerous detoxification strategies to suppress host reactive oxygen species (ROS), but their coordination is not well‐understood.Here, we show that Sirt5‐mediated protein desuccinylation in Magnaporthe oryzae is central to host ROS detoxification. SIRT5 encodes a desuccinylase important for virulence via adaptation to host oxidative stress. Quantitative proteomics analysis identified a large number of succinylated proteins targeted by Sirt5, most of which were mitochondrial proteins involved in oxidative phosphorylation, TCA cycle, and fatty acid oxidation.Deletion of SIRT5 resulted in hypersuccinylation of detoxification‐related enzymes, and significant reduction in NADPH : NADP+ and GSH : GSSG ratios, disrupting redox balance and impeding invasive growth. Sirt5 desuccinylated thioredoxin Trx2 and glutathione peroxidase Hyr1 to activate their enzyme activity, likely by affecting proper folding.Altogether, this work demonstrates the importance of Sirt5‐mediated desuccinylation in controlling fungal process required for detoxifying host ROS during M. oryzae infection. [ABSTRACT FROM AUTHOR]

Exposure to a hypobaric hypoxic environment at high altitudes can lead to liver injury, and mounting evidence indicates that pyroptosis and inflammation play important roles in liver injury. Curcumin (Cur) can inhibit pyroptosis and inflammation. Therefore, our purpose here was to clarify the mechanism underlying the protective effect of nanocurcumin (Ncur) and Cur in a rat model of high altitude‐associated acute liver injury. Eighty healthy rats were selected and exposed to different altitudes (6000 or 7000 m) for 0, 24, 48, or 72 h. Fifty normal healthy rats were divided into normal control, high‐altitude control, salidroside (40 mg/kg [Sal‐40]), Cur (200 mg/kg [Cur‐200]), and Ncur (25 mg/kg [Ncur‐25]) groups and exposed to a high‐altitude hypobaric hypoxic environment (48 h, 7000 m). Serum‐liver enzyme activities (alanine transaminase, aspartate transaminase, and lactate dehydrogenase were detected and histopathology of liver injury was evaluated by hematoxylin and eosin staining, and inflammatory factors were detected in liver tissues by enzyme‐linked immunosorbent assays. Pyroptosis‐associated proteins (gasdermin D, gasdermin D N‐terminal [GSDMD‐N], pro‐Caspase‐1, and cleaved‐Caspase‐1 [cleaved‐Casp1]) and inflammation‐associated proteins (nuclear factor‐κB [NF‐κB], phospho‐NF‐κB [P‐NF‐κB], and high‐mobility group protein B1 [HMGB1]) levels were analyzed by immunoblotting. Ncur and Cur inhibited increased serum‐liver enzyme activities, alleviated liver injury in rats caused by high‐altitude hypobaric hypoxic exposure, and downregulated inflammatory factors, including tumor necrosis factor‐α, interleukin (IL)‐1β, IL‐6, and IL‐18, in rat liver tissues. The level of P‐NF‐κB, GSDMD‐N, cleaved‐Casp1, and HMGB1 in rat liver tissues increased significantly after high‐altitude exposure. Ncur and Cur downregulated P‐NF‐κB, GSDMD‐N, cleaved‐Casp‐1, and HMGB1. Ncur and Cur may inhibit inflammatory responses and pyroptosis in a rat model of high altitude‐associated acute liver injury. [ABSTRACT FROM AUTHOR]

ABSTRACT The micro‐morphology of photocatalytic materials has a great influence on their photocatalytic performance. Quantum dots can provide the plasmon resonance effect and broaden the wavelength range of light absorption. In this study, a kind of 3D spherical flower‐like structure was constructed by self‐assembly of 2D nanosheets, the Bi2S3 particles with 5 ± 1 nm diameter were modified on the surfaces of Bi2O2CO3 nanosheets to prepare the Bi2S3/Bi2O2CO3 composite. The energy level difference (0.45 eV) between the conduction bands (CB) of Bi2S3 and Bi2O2CO3 led to which the e− was transferred to CB of Bi2O2CO3. The energy level difference (0.83 eV) between the CB of Bi2O2CO3 and the valence band (VB) of Bi2S3 was much smaller than the band gap (1.28 eV) of Bi2S3, and it led to which the electrons on the CB of Bi2O2CO3 were recombined with the holes on the VB of Bi2S3. A kind of innovative type heterojunction was constructed between Bi2S3 and Bi2O2CO3, which encouraged the photogenerated h+ and ·OH to be located on the VB of Bi2O2CO3 with the strongest oxidation potential, the prepared material showed excellent performance for the photodegradation of RhB, and the active groups were also controlled in the photocatalysis process. [ABSTRACT FROM AUTHOR]

In the domain of high‐performance short‐wave infrared (SWIR) photodetection and imaging, existing technologies predominantly utilize single‐crystal germanium and III‐V semiconductors. Despite their efficacy, these materials are encumbered by laborious synthesis and complex fabrication demands. In this study, the synthesis of large‐area, high‐crystallinity Se0.2Te0.8 thin films through a CMOS‐compatible vacuum thermal evaporation process is reported. A high‐speed, broad‐spectrum photodetector engineered with an innovative Gr/Se0.2Te0.8/GaAs vertical heterostructure is presented, which capitalizes on the augmented carrier mobility and employs graphene innovatively as both a carrier collection interface and an electrode. This configuration facilitates a remarkably swift response time of 800 ns/1 µs at the crucial 1310 nm wavelength for optical communications. Moreover, the fabrication of a 5 × 5 array device demonstrates substantial SWIR imaging capabilities at ambient conditions, marking a paradigm shift in uncooled infrared imaging and communication technologies. This work not only extends the boundaries of SWIR photodetector performance but also underscores the potential of novel material systems in high‐speed optical applications. [ABSTRACT FROM AUTHOR]