The protein phosphatase PC1 dephosphorylates and deactivates CatC to negatively regulate H2O2 homeostasis and salt tolerance in rice.

Catalase (CAT) is often phosphorylated and activated by protein kinases to maintain hydrogen peroxide (H2O2) homeostasis and protect cells against stresses, but whether and how CAT is switched off by protein phosphatases remains inconclusive. Here, we identified a manganese (Mn2+)-dependent protein phosphatase, which we named PHOSPHATASE OF CATALASE 1 (PC1), from rice (Oryza sativa L.) that negatively regulates salt and oxidative stress tolerance. PC1 specifically dephosphorylates CatC at Ser-9 to inhibit its tetramerization and thus activity in the peroxisome. PC1 overexpressing lines exhibited hypersensitivity to salt and oxidative stresses with a lower phospho-serine level of CATs. Phosphatase activity and seminal root growth assays indicated that PC1 promotes growth and plays a vital role during the transition from salt stress to normal growth conditions. Our findings demonstrate that PC1 acts as a molecular switch to dephosphorylate and deactivate CatC and negatively regulate H2O2 homeostasis and salt tolerance in rice. Moreover, knockout of PC1 not only improved H2O2-scavenging capacity and salt tolerance but also limited rice grain yield loss under salt stress conditions. Together, these results shed light on the mechanisms that switch off CAT and provide a strategy for breeding highly salt-tolerant rice.

GLK transcription factors accompany ELONGATED HYPOCOTYL5 to orchestrate light-induced seedling development in Arabidopsis.

Light-induced de-etiolation is an important aspect of seedling photomorphogenesis. GOLDEN2 LIKE (GLK) transcriptional regulators are involved in chloroplast development, but to what extent they participate in photomorphogenesis is not clear. Here, we show that ELONGATED HYPOCOTYL5 (HY5) binds to GLK promoters to activate their expression, and also interacts with GLK proteins in Arabidopsis (Arabidopsis thaliana). The chlorophyll content in the de-etiolating Arabidopsis seedlings of the hy5 glk2 double mutants was lower than that in the hy5 single mutant. GLKs inhibited hypocotyl elongation, and the phenotype could superimpose on the hy5 phenotype. Correspondingly, GLK2 regulated the expression of photosynthesis and cell elongation genes partially independent of HY5. Before exposure to light, DE-ETIOLATED 1 (DET1) affected accumulation of GLK proteins. The enhanced etioplast development and photosystem gene expression observed in the det1 mutant were attenuated in the det1 glk2 double mutant. Our study reveals that GLKs act downstream of HY5, or additive to HY5, and are likely quantitatively adjusted by DET1, to orchestrate multiple developmental traits during the light-induced skotomorphogenesis-to-photomorphogenesis transition in Arabidopsis.

Aristolochia mimics stink bugs to repel vertebrate herbivores via TRPA1 activation.

Mimicry is the phenomenon in which one species (the mimic) closely resembles another (the model), enhancing its own fitness by deceiving a third party into interacting with it as if it were the model. In plants, mimicry is used primarily to gain fitness by withholding rewards from mutualists or deterring herbivores cost-effectively. While extensive work has been documented on putative defence mimicry, limited investigation has been conducted in the field of chemical mimicry. In this study, we used field experiments, chemical analyses, behavioural assays, and electrophysiology, to test the hypothesis that the birthwort Aristolochia delavayi employs chemical mimicry by releasing leaf scent that closely resembles stink bug defensive compounds and repels vertebrate herbivores. We show that A. delavayi leaf scent is chemically and functionally similar to the generalized defensive volatiles of stink bugs and that the scent effectively deters vertebrate herbivores, likely through the activation of TRPA1 channels via (E)-2-alkenal compounds. This study provides an unequivocal example of chemical mimicry in plants, revealing intricate dynamics between plants and vertebrate herbivores. Our study underscores the potency of chemical volatiles in countering vertebrate herbivory, urging further research to uncover their potentially underestimated importance.

Cell division in the shoot apical meristem is a trigger for miR156 decline and vegetative phase transition in Arabidopsis.

What determines the rate at which a multicellular organism matures is a fundamental question in biology. In plants, the decline of miR156 with age serves as an intrinsic, evolutionarily conserved timer for the juvenile-to-adult phase transition. However, the way in which age regulates miR156 abundance is poorly understood. Here, we show that the rate of decline in miR156 is correlated with developmental age rather than chronological age. Mechanistically, we found that cell division in the apical meristem is a trigger for miR156 decline. The transcriptional activity of MIR156 genes is gradually attenuated by the deposition of the repressive histone mark H3K27me3 along with cell division. Our findings thus provide a plausible explanation of why the maturation program of a multicellular organism is unidirectional and irreversible under normal growth conditions and suggest that cell quiescence is the fountain of youth in plants.

Reduced microbial stability in the active layer is associated with carbon loss under alpine permafrost degradation.

Permafrost degradation may induce soil carbon (C) loss, critical for global C cycling, and be mediated by microbes. Despite larger C stored within the active layer of permafrost regions, which are more affected by warming, and the critical roles of Qinghai-Tibet Plateau in C cycling, most previous studies focused on the permafrost layer and in high-latitude areas. We demonstrate in situ that permafrost degradation alters the diversity and potentially decreases the stability of active layer microbial communities. These changes are associated with soil C loss and potentially a positive C feedback. This study provides insights into microbial-mediated mechanisms responsible for C loss within the active layer in degraded permafrost, aiding in the modeling of C emission under future scenarios.

Synergistic Radiation Effects in PPD CMOS Image Sensors Induced by Neutron Displacement Damage and Gamma Ionization Damage.

The synergistic effects on the 0.18 µm PPD CISs induced by neutron displacement damage and gamma ionization damage are investigated. The typical characterizations of the CISs induced by the neutron displacement damage and gamma ionization damage are presented separately. The CISs are irradiated by reactor neutron beams up to 1 × 1011 n/cm2 (1 MeV neutron equivalent fluence) and 60Co γ-rays up to the total ionizing dose level of 200 krad(Si) with different sequential order. The experimental results show that the mean dark signal increase in the CISs induced by reactor neutron radiation has not been influenced by previous 60Co γ-ray radiation. However, the mean dark signal increase in the CISs induced by 60Co γ-ray radiation has been remarkably influenced by previous reactor neutron radiation. The synergistic effects on the PPD CISs are discussed by combining the experimental results and the TCAD simulation results of radiation damage.

Algorithm for the reconstruction of the parotid region: a single institution experience.

OBJECTIVE: This study aims to discuss the characteristics and treatment methods of malignant tumors in the parotid region, as well as the therapeutic effects of immediate free flap reconstruction of soft tissue for postoperative defects. MATERIALS AND METHODS: A retrospective review was conducted on 11 cases of soft tissue flap reconstruction for postoperative defects following the resection of malignant tumors in the parotid region. Statistical analysis was performed based on clinical data. RESULTS: Among the 11 cases of malignant tumors in the parotid region, there were 2 cases of secretory carcinoma (SC) of the salivary gland, 2 cases of squamous cell carcinoma (SCC), 2 cases of carcinosarcoma, 1 case of mucoepidermoid carcinoma (MEC), 1 case of epithelial-myoepithelial carcinoma (EMC), 1 case of salivary duct carcinoma (SDC), 1 case of basal cell carcinoma (BCC), and 1 case of osteosarcoma. Among these cases, 4 were initial diagnoses and 7 were recurrent tumors. The defect repairs involved: 8 cases with anterolateral thigh free flap (ALTF), 2 cases with pectoralis major muscle flaps, and 1 case with forearm flap. The size of the flaps ranged from approximately 1 cm × 3 cm to 7 cm × 15 cm. The recipient vessels included: 4 cases with the facial artery, 4 cases with the superior thyroid artery, and 1 case with the external carotid artery. The ratio of recipient vein anastomosis was: 57% for branches of the internal jugular vein, 29% for the facial vein, and 14% for the external jugular vein. Among the 8 cases that underwent neck lymph node dissection, one case showed lymph node metastasis on pathological examination. In the initial diagnosis cases, 2 cases received postoperative radiotherapy, and 1 case received 125I seed implantation therapeutic treatment after experiencing two recurrences. Postoperative follow-up revealed that 2 cases underwent reoperation due to local tumor recurrence, and there were 2 cases lost to follow-up. The survival outcomes after treatment included: one case of distant metastasis and one case of death from non-cancerous diseases. CONCLUSION: Immediate soft tissue flap reconstruction is an important and valuable option to address postoperative defects in patients afflicted with malignant tumors in the parotid region.

Observation of Anomalous Orbital Angular Momentum Transfer in Parametric Nonlinearity.

Orbital angular momentum (OAM) conservation plays an important role in shaping and controlling structured light with nonlinear optics. The OAM of a beam originating from three-wave mixing should be the sum or difference of the other two inputs because no light-matter OAM exchange occurs in parametric nonlinear interactions. Here, we report anomalous OAM transfer in parametric upconversion, in which a Hermite-Gauss mode signal interacts with a specially engineered pump capable of astigmatic transformation, resulting in Laguerre-Gaussian mode sum-frequency generation (SFG). The anomaly here refers to the fact that the pump and signal both carry no net OAM, while their SFG does. We reveal experimentally that there is also an OAM inflow to the residual pump, having the same amount of that to the SFG but with the opposite sign, and thus holds system OAM conservation. This unexpected OAM selection rule improves our understanding of OAM transfer among interacting waves and may inspire new ideas for controlling OAM states via nonlinear optics.

Design, Synthesis and Characterization of Palladium-Functionalized Covalent Organic Framework and Its Application as Heterogeneous Catalysis for C-H Arylation of Azoles.

A novel triazine-based covalent organic framework (TFPT-Bz COF) has been constructed by the condensation of 2,4,6-tris(5-formyl-2-pyridinoxy)-1,3,5-triazine (TFPT) and benzidine (BZ) with deep eutectic solvent (DES) as the reaction medium. After the introduction of Pd ions through strong coordination to TFPT-Bz COF matrix, the constructed TFPT-Bz COF/Pd composite exhibited excellent catalytic activity for C-H arylation of azoles with aryl halides in 2-methyltetrahydrofuran. The protocol allows the arylation of a variety of substituted azoles with diverse aryl halides in high to excellent yield. Moreover, the TFPT-Bz COF/Pd catalyst can be recycled several times without significantly reducing its activity.

Untangling determinants of gut microbiota and tumor immunologic status through a multi-omics approach in colorectal cancer.

The changes in gut microbiota have been implicated in colorectal cancer (CRC). The interplays between the host and gut microbiota remain largely unclear, and few studies have investigated these interplays using integrative multi-omics data. In this study, large-scale multi-comic datasets, including microbiome, metabolome, bulk transcriptomics and single cell RNA sequencing of CRC patients, were analyzed individually and integrated through advanced bioinformatics methods. We further examined the clinical relevance of these findings in the mice recolonized with microbiota from human. We found that CRC patients had distinct microbiota compositions compared to healthy controls. A machine-learning model was developed with 28 biomarkers for detection of CRC, which had high accuracy and clinical applicability. We identified multiple significant correlations between genera and well-characterized genes, suggesting the potential role of gut microbiota in tumor immunity. Further analysis showed that specific metabolites worked as profound communicators between these genera and tumor immunity. Integrating microbiota and metabolome perspectives, we cataloged gut taxonomic and metabolomic features that represented the key multi-omics signature of CRC. Furthermore, gut microbiota transplanted from CRC patients compromised the response of CRC to immunotherapy. These phenotypes were strongly associated with the alterations in gut microbiota, immune cell infiltration as well as multiple metabolic pathways. The comprehensive interplays across multi-comic data of CRC might explain how gut microbiota influenced tumor immunity. Hence, we proposed that modifying the CRC microbiota using healthy donors might serve as a promising strategy to improve response to immunotherapy.

Host ALDH2 deficiency aggravates nonalcoholic steatohepatitis through gut-liver axis.

Nonalcoholic steatohepatitis (NASH) is the major cause of liver dysfunction. Animal and population studies have shown that mitochondrial aldehyde dehydrogenase (ALDH2) is implicated in fatty liver disease. However, the role of ALDH2 in NASH and the underlying mechanisms remains unclear. To address this issue, ALDH2 knockout (ALDH2-/-) mice and wild-type littermate mice were fed a methionine-and choline-deficient (MCD) diet to induce a NASH model. Fecal, serum, and liver samples were collected and analyzed to investigate the impact of the gut microbiota and bile acids on this process. We found that MCD-fed ALDH2-/- mice exhibited increased serum pro-inflammation cytokines, hepatic inflammation and fat accumulation than their wild-type littermates. MCD-fed ALDH2-/- mice exhibited worsened MCD-induced intestinal inflammation and barrier damage, and gut microbiota disorder. Furthermore, mice receiving microbiota from MCD-fed ALDH2-/- mice had increased severity of NASH compared to those receiving microbiota from MCD-fed wild-type mice. Notably, the intestinal Lactobacillus was significantly reduced in MCD-fed ALDH2-/- mice, and gavage with Lactobacillus cocktail significantly improved MCD-induced NASH. Finally, we found that ALDH2-/- mice had reduced levels of bile salt hydrolase and specific bile acids, especially lithocholic acid (LCA), accompanied by downregulated expression of the intestinal FXR-FGF15 pathway. Supplementation of LCA in ALDH2-/- mice upregulated intestinal FXR-FGF15 pathway and alleviated NASH. In summary, ALDH2 plays a critical role in the development of NASH through modulation of gut microbiota and bile acid. The findings suggest that supplementing with Lactobacillus or LCA could be a promising therapeutic approach for treating NASH exacerbated by ALDH2 deficiency.

Hybridization and divergent climatic preferences drive divergence of two allopatric Gentiana species on the Qinghai-Tibet Plateau.

BACKGROUND AND AIMS: Exploring how species diverge is vital for understanding the drivers of speciation. Factors such as geographical separation and ecological selection, hybridization, polyploidization and shifts in mating system are all major mechanisms of plant speciation, but their contributions to divergence are rarely well understood. Here we test these mechanisms in two plant species, Gentiana lhassica and G. hoae, with the goal of understanding recent allopatric species divergence on the Qinghai-Tibet Plateau (QTP). METHODS: We performed Bayesian clustering, phylogenetic analysis and estimates of hybridization using 561 302 nuclear genomic single nucleotide polymorphisms (SNPs). We performed redundancy analysis, and identified and annotated species-specific SNPs (ssSNPs) to explore the association between climatic preference and genetic divergence. We also estimated genome sizes using flow cytometry to test for overlooked polyploidy. KEY RESULTS: Genomic evidence confirms that G. lhassica and G. hoae are closely related but distinct species, while genome size estimates show divergence occurred without polyploidy. Gentiana hoae has significantly higher average FIS values than G. lhassica. Population clustering based on genomic SNPs shows no signature of recent hybridization, but each species is characterized by a distinct history of hybridization with congeners that has shaped genome-wide variation. Gentiana lhassica has captured the chloroplast and experienced introgression with a divergent gentian species, while G. hoae has experienced recurrent hybridization with related taxa. Species distribution modelling suggested range overlap in the Last Interglacial Period, while redundancy analysis showed that precipitation and temperature are the major climatic differences explaining the separation of the species. The species differ by 2993 ssSNPs, with genome annotation showing missense variants in genes involved in stress resistance. CONCLUSIONS: This study suggests that the distinctiveness of these species on the QTP is driven by a combination of hybridization, geographical isolation, mating system differences and evolution of divergent climatic preferences.

Bacterial communities associated with mushrooms in the Qinghai-Tibet Plateau are shaped by soil parameters.

Fungi capable of producing fruit bodies are essential food and medicine resources. Despite recent advances in the study of microbial communities in mycorrhizospheres, little is known about the bacterial communities contained in fruit bodies. Using high-throughput sequencing, we investigated the bacterial communities in four species of mushrooms located on the alpine meadow and saline-alkali soil of the Qinghai-Tibet Plateau (QTP). Proteobacteria (51.7% on average) and Actinobacteria (28.2% on average) were the dominant phyla in all of the sampled fairy ring fruit bodies, and Acidobacteria (27.5% on average) and Proteobacteria (25.7% on average) dominated their adjacent soils. For the Agria. Bitorquis, Actinobacteria was the dominant phylum in its fruit body (67.5% on average) and adjacent soils (65.9% on average). The alpha diversity (i.e., Chao1, Shannon, Richness, and Simpson indexes) of the bacterial communities in the fruit bodies were significantly lower than those in the soil samples. All of the fungi shared more than half of their bacterial phyla and 16.2% of their total operational taxonomic units (OTUs) with their adjacent soil. Moreover, NH4+ and pH were the key factors associated with bacterial communities in the fruit bodies and soils, respectively. These results indicate that the fungi tend to create a unique niche that selects for specific members of the bacterial community. Using culture-dependent methods, we also isolated 27 bacterial species belonging to three phyla and five classes from fruit bodies and soils. The strains isolated will be useful for future research on interactions between mushroom-forming fungi and their bacterial endosymbionts.

Alloying Matters for Ordering: Synthesis of Highly Ordered PtCo Intermetallic Catalysts for Fuel Cells.

Porous carbon-supported atomically ordered intermetallic compounds (IMCs) are promising electrocatalysts in boosting oxygen reduction reaction (ORR) for fuel cell applications. However, the formation mechanism of IMC structures under high temperatures is poorly understood, which hampers the synthesis of highly ordered IMC catalysts with promoted ORR performance. Here, we employ high-temperature X-ray diffraction and energy-dispersive spectroscopic elemental mapping techniques to study the formation process of IMCs, by taking PtCo for example, in an industry-relevant impregnation synthesis. We find that high-temperature annealing is crucial in promoting the formation of alloy particles with a stoichiometric Co/Pt ratio, which in turn is the precondition for transforming the disordered alloys to ordered intermetallic structures at a relatively low temperature. Based on the findings, we accordingly synthesize highly ordered L10-type PtCo catalysts with a remarkable ORR performance in fuel cells.

Preparation and performance of aerogel-based BiOI/TiO2 heterojunction photoelectrocatalytic electrodes.

TiO2/BiOI/CA electrodes with improved conductivity, reduced photoelectron-hole recombination rates, and increased reaction sites based on p-n type heterojunctions were constructed on carbon aerogels (CA) as photoelectrode substrates. Characterization based on ultraviolet-visible diffuse reflectance spectroscopy, photocurrent measurements, and impedance analysis showed that the TiO2/BiOI/CA photoelectrode with a Ti/Bi mole ratio of 0.4 exhibited the best visible light absorption, lowest photogenerated electron-hole pair recombination rate, and strongest photocatalytic degradation, with 90.4% degradation of phenol under 120 min of light. Moreover, the stability of this electrode remained at a high level. This was mainly because the energy levels of TiO2 and BiOI matched each other and the p-n heterojunction formed adjusted the energy band structure of the composite material, widened the electron transfer path, formed an internal electric field between the phase interfaces, had a higher electron transfer rate, and reduced the photogenerated electron-hole recombination rate. Since ˙OH and ˙O2- are the main active substances in the degradation of phenol, the TiO2/BiOI/CA photoelectrodes had higher degradation efficiency than BiOI/CA electrodes. This study provides a unique concept for the treatment of organic pollutant wastewater and electrode design for photoelectrocatalysis.

Microtiter plate-based chemistry and in situ screening: SuFEx-enabled lead discovery of selective AChE inhibitors.

Sulphur fluoride exchange (SuFEx) is a category of click chemistry that enables covalent linking of modular units through sulphur connective hubs. Here, we reported an efficient synthesis and in situ screening method for building a library of sulphonamides on the picomolar scale by SuFEx reaction between a sulphonyl fluoride (RSO2F) core and primary or secondary amines. This biocompatible SuFEx reaction would allow us to rapidly synthesise sulphonamide molecules, and evaluate their ChE inhibitory activity. Compound T14-A24 was identified as a reversible, competitive, and selective AChE inhibitor (Ki = 22 nM). The drug-like evaluation showed that T14-A24 had benign BBB penetration, remarkable neuroprotective effect, and safe toxicological profile. In vivo behavioural study showed that T14-A24 treatment improved the Aß1 - 42-induced cognitive impairment, significantly prevented the effects of Aß1 - 42 toxicity. Therefore, this SuFEx click reaction can accelerate the discovery of lead compounds.

Optofluidic tunable broadband distributed Bragg reflector based on liquid crystal polymer composites.

A dynamically reconfigurable liquid crystal (LC) photonic device is an important research field in modern LC photonics. We present a type of continuously tunable distributed Bragg reflector (DBR) based on LC polymer composites modulated via a novel optofluidic method. LC-templated DBR films are fabricated by photopolymerization under visible standing wave interference. The influences of the incident angle, incident light intensity, and content of ethanol as a pore-forming additive on the reflection behavior are discussed in detail. Then, the LC-templated DBR films are integrated into microfluidic channels and reversibly refilled by different organic solvents. The reconfigurable characteristics of optofluidic DBRs were demonstrated by changing the average refractive index (RI) of the mixed liquids and adjusting the flow rates, resulting in the dynamic and continuous variation of the reflection band within a specific visible light band. It is anticipated that the prototype optofluidic LC device will hopefully be applied to some specific scenarios where conventional means of regulation, such as electric, optical, and temperature fields, are unsuitable and possibly boost the development of microfluidic analysis techniques based on structural color.

High-Temperature Synthesis of Carbon-Supported Bimetallic Nanocluster Catalysts by Enlarging the Interparticle Distance.

Supported bimetallic nanoparticle catalysts with small size have attracted wide research attention in catalysis but are difficult to synthesize because high-temperature annealing required for alloying inevitably accelerates metal sintering and leads to larger particles. Here, we report a simple and scalable "critical interparticle distance" method for the synthesis of a family of bimetallic nanocluster catalysts with an average particle size of only 1.5 nm by using large-surface-area carbon black supports at high temperatures, which consist of 12 diverse combinations of 3 noble metals (Pt, Ru, and Rh) and 4 other metals (Cr, Fe, Zr, and Sn). In this strategy, high-temperature treatments ensure the formation of alloyed bimetallic nanoparticles and enlargement of the interparticle distance on high-surface-area supports significantly suppresses metal sintering. The prepared ultrafine Pt2Sn and RuSn nanocluster catalysts exhibited enhanced performance in catalyzing the synthesis of aromatic secondary amines and the selective hydrogenation of furfural, respectively.

Pentacoordinate Al3+ Sites Anchoring Synthesis of Palladium Intermetallic Catalysts on Al2O3 Supports.

Size control of supported Pd-based intermetallic nanoparticles (i-NPs) remains a major challenge because the required high-temperature annealing for atomic diffusion and ordering easily causes metal sintering. Here, we described a pentacoordinate Al3+ site (Al3+penta) anchoring approach for the preparation of Pd-based i-NPs with controlled size, which takes advantage of the strong chemical interaction between Al3+penta sites and Pd-based i-NPs to realize size control. We synthesized six types of Pd-based i-NPs, and four of them can remain an average particle size of <6 nm. Furthermore, one of our prepared Pd-based i-NPs (that is, Pd3Pb) demonstrated outstanding performance in catalyzing the semihydrogenation of phenylacetylene.

Efficient degradation of VOCs using semi-coke activated carbon loaded ternary Z-scheme heterojunction photocatalyst BiVO4-BiPO4-g-C3N4 under visible light irradiation.

The coal chemical industry generates large amounts of solid waste and volatile organic compounds (VOCs). In this study, the solid waste semi-coke powder obtained in the semi-coke production process was used as a raw material to prepare high-specific surface area semi-coke activated carbon (SAC) by a carbonization and activation process, and a ternary z-scheme heterojunction photocatalyst with high catalytic performance was loaded for synergistic treatment by adsorption and photodegradation to achieve waste treatment with waste. The prepared semi-coke activated carbon has a specific surface area of 619.27 m2 g-1, which can achieve effective adsorption of VOCs. The ternary z-scheme heterojunction photocatalyst BiPO4-BiVO4-g-C3N4 (PVCN) was supported on a semi-coke activated carbon substrate by a one-step sol-gel method. Based on the synergistic effect of adsorption and photocatalysis, the obtained PVCN/SAC material can degrade toluene by 85.6% within 130 minutes under simulated sunlight irradiation, which is 2.43 times that of pure photocatalyst. The rate of degrading toluene can be increased by 4.43 times. Capture experiments showed that superoxide radicals (˙O2-) and hydroxyl radicals (˙OH) were the key active species in the degradation pathway. Even after five cycles, the material maintained 81.6% of the degradation performance. In this work, we deeply investigate the mechanism of semi-coke activated carbon as a matrix for enhancing photocatalytic degradation performance. The findings of this work provide new insights into the efficient degradation of VOCs and provide a good theoretical basis for the development of high-performance photocatalysts.