Release of a ubiquitin brake activates OsCERK1-triggered immunity in rice.

Plant pattern-recognition receptors perceive microorganism-associated molecular patterns to activate immune signalling1,2. Activation of the pattern-recognition receptor kinase CERK1 is essential for immunity, but tight inhibition of receptor kinases in the absence of pathogen is crucial to prevent autoimmunity3,4. Here we find that the U-box ubiquitin E3 ligase OsCIE1 acts as a molecular brake to inhibit OsCERK1 in rice. During homeostasis, OsCIE1 ubiquitinates OsCERK1, reducing its kinase activity. In the presence of the microorganism-associated molecular pattern chitin, active OsCERK1 phosphorylates OsCIE1 and blocks its E3 ligase activity, thus releasing the brake and promoting immunity. Phosphorylation of a serine within the U-box of OsCIE1 prevents its interaction with E2 ubiquitin-conjugating enzymes and serves as a phosphorylation switch. This phosphorylation site is conserved in E3 ligases from plants to animals. Our work identifies a ligand-released brake that enables dynamic immune regulation.

Nomogram based on lymphocyte-associated inflammatory indexes predicts portal vein thrombosis after splenectomy with esophagogastric devascularization.

OBJECTIVE: The relationship between lymphocyte-associated inflammatory indices and portal vein thrombosis (PVT) following splenectomy combined with esophagogastric devascularization (SED) is currently unclear. This study aims to investigate the association between these inflammatory indices and PVT, and to develop a nomogram based on these indices to predict the risk of PVT after SED, providing an early warning tool for clinical practice. METHODS: We conducted a retrospective analysis of clinical data from 131 cirrhotic patients who underwent SED at Lanzhou University's Second Hospital between January 2014 and January 2024. Independent risk factors for PVT were identified through univariate and multivariate logistic regression analyses, and the best variables were selected using the Akaike Information Criterion (AIC) to construct the nomogram. The model's predictive performance was assessed through receiver operating characteristic (ROC), calibration, decision, and clinical impact curves, with bootstrap resampling used for internal validation. RESULTS: The final model incorporated five variables: splenic vein diameter (SVD), D-Dimer, platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), and red cell distribution width-to-lymphocyte ratio (RLR), achieving an area under the curve (AUC) of 0.807, demonstrating high predictive accuracy. Calibration and decision curves demonstrated good calibration and significant clinical benefits. The model exhibited good stability through internal validation. CONCLUSION: The nomogram model based on lymphocyte-associated inflammatory indices effectively predicts the risk of portal vein thrombosis after SED, demonstrating high accuracy and clinical utility. Further validation in larger, multicenter studies is needed.

Pressure Tunable van Hove Singularities of Twisted Bilayer Graphene.

The giant light-matter interaction induced by van Hove singularities (vHSs) of twisted bilayer graphene (tBLG) is responsible for enhanced optical absorption and strong photoresponse. Here, we investigated the evolution of vHSs in tBLG under pressure by using Raman spectroscopy. Pressure not only induces a blue shift of the G/R band but also tunes the intensity of the G/R band. The blue shift of the G/R band is due to the reduction of the in-plane lattice constant, and the variation of the G/R band intensity is due to the vHSs' shift of tBLG. Moreover, the main band in the absorption spectrum of tBLG is attributed to multiple transitions from valence to conduction bands. Because the ratio of R to G band intensity increases under pressure and the origins of R and G bands are different, we claim that pressure enhances intervalley electron scattering. This study paves the way for pressure engineering of vHS and the corresponding photon-electron-phonon interaction in tBLG.

Confining isolated chromophores for highly efficient blue phosphorescence.

High-efficiency blue phosphorescence emission is essential for organic optoelectronic applications. However, synthesizing heavy-atom-free organic systems having high triplet energy levels and suppressed non-radiative transitions-key requirements for efficient blue phosphorescence-has proved difficult. Here we demonstrate a simple chemical strategy for achieving high-performance blue phosphors, based on confining isolated chromophores in ionic crystals. Formation of high-density ionic bonds between the cations of ionic crystals and the carboxylic acid groups of the chromophores leads to a segregated molecular arrangement with negligible inter-chromophore interactions. We show that tunable phosphorescence from blue to deep blue with a maximum phosphorescence efficiency of 96.5% can be achieved by varying the charged chromophores and their counterions. Moreover, these phosphorescent materials enable rapid, high-throughput data encryption, fingerprint identification and afterglow display. This work will facilitate the design of high-efficiency blue organic phosphors and extend the domain of organic phosphorescence to new applications.

Wnt/ß-Catenin signaling pathway in hepatocellular carcinoma: pathogenic role and therapeutic target.

Hepatocellular carcinoma (HCC) is the most common primary malignant liver tumor and one of the leading causes of cancer-related deaths worldwide. The Wnt/ß-Catenin signaling pathway is a highly conserved pathway involved in several biological processes, including the improper regulation that leads to the tumorigenesis and progression of cancer. New studies have found that abnormal activation of the Wnt/ß-Catenin signaling pathway is a major cause of HCC tumorigenesis, progression, and resistance to therapy. New perspectives and approaches to treating HCC will arise from understanding this pathway. This article offers a thorough analysis of the Wnt/ß-Catenin signaling pathway's function and its therapeutic implications in HCC.

The Sorting Nexin Genes ChSNX4 and ChSNX41 Are Required for Reproductive Development, Stress Adaption and Virulence in Cochliobolus heterostrophus.

Sorting nexins are a conserved protein family involved in many cellular processes in fungi, and the function of sorting nexin Snx4 (Atg24) and Snx41 (Atg20) in Cochliobolus heterostrophus was not clear. The ΔChsnx4 and ΔChsnx41 mutants were generated by a PCR-based marker method to determine the roles of Snx4 and Snx41 in reproductive development, stress adaption, and virulence in C. heterostrophus. Compared with the wild-type strain, the ΔChsnx4 and ΔChsnx41 mutants exhibited obvious changes in vegetative growth and in morphology of conidia. In addition, the conidiation, appressorium formation, and virulence of snx4 and snx41 mutants were dramatically reduced. Moreover, ΔChsnx4 and ΔChsnx41 mutants were more sensitive to oxidative stress (menadione and H2O2), cell wall integrity stress (Congo red and calcofluor white), fungicides, and isothiocyanates. All the phenotypes mentioned above were restored in complemented strains. In addition, ChSnx4 and ChSnx41 were proven to interact with each other through yeast two-hybrid. Taken together, these findings indicated that ChSNX4 and ChSNX41 were important for fungal growth, asexual development, stress adaption, and virulence in C. heterostrophus.

Epitaxial growth of large-grain-size ferromagnetic monolayer CrI3 for valley Zeeman splitting enhancement.

Two-dimensional (2D) magnetic CrI3 has received considerable research attention because of its intrinsic features, including insulation, Ising ferromagnetism, and stacking-order-dependent magnetism, as well as potential in spintronic applications. However, the current strategy for the production of ambient-unstable CrI3 thin layer is limited to mechanical exfoliation, which normally suffers from uncontrollable layer thickness, small size, and low yet unpredictable yield. Here, via a confined vapor epitaxy (CVE) method, we demonstrate the mass production of flower-like CrI3 monolayers on mica. Interestingly, we discovered the crucial role of K ions on the mica surface in determining the morphology of monolayer CrI3, reacting with precursors to form a KIx buffer layer. Meanwhile, the transport agent affects the thickness and size of the as-grown CrI3. Moreover, the Curie temperature of CrI3 is greatly affected by the interaction between CrI3 and the substrate. The monolayer CrI3 on mica could act as a magnetic substrate for valley Zeeman splitting enhancement of WSe2. We reckon our work represents a major advancement in the mass production of monolayer 2D CrI3 and anticipate that our growth strategy may be extended to other transition metal halides.

Stability and Phase Transition of Metastable Black Arsenic under High Pressure.

Black arsenic (bAs) is a metastable phase of arsenic that has attracted increasing interest owing to its layered structure, tunable band gap, high carrier mobility, and large on/off ratio. Here, we systematically investigated the high-pressure behaviors of bAs up to ∼14 GPa. A phase transition from bAs to gray arsenic (gAs) occurred at critical pressure of 3.48 GPa, and the bAs and gAs coexisted between 3.48 and 5.37 GPa before bAs completely converted to gAs above 5.37 GPa. The structure was reversible for bAs after pressure was released from about 1-3 GPa, indicating the stability of bAs at pressures less than the critical pressure. At pressures above 5.37 GPa, bAs transformed to gAs and remained gAs after pressure was released. Molecular dynamics (MD) simulation was performed to explain the phase transition mechanism. This work provides insights into the phase stability and phase transition of metastable bAs under high pressure.

Direct-Indirect Transition of Pressurized Two-Dimensional Halide Perovskite: Role of Benzene Ring Stack Ordering.

Two-dimensional (2D) hybrid organic-inorganic metal halide perovskites (HOIPs) with considerably hydrophobic phenyl ethylammonium (PEA) organic cations have been used in highly efficient solar cells and LEDs, which are stable and enjoy a long lifetime, even when exposed to moisture. Different from other 2D HOIPs with alkyl amine cations, a benzene ring is present in the PEA cation. Until recently, an understanding of the effects of PEA on the structural, electronic, and optical properties of 2D HOIPs under pressure has remained limited. We find that there is a direct-indirect band gap transition at around 5.8 GPa and that the direct band gap recovers when the pressure is released. The stacking order of the benzene rings in the PEA cation plays a critical role in the mechanical and electronic properties. Our present work demonstrates that 2D HOIPs with organic cations containing benzene rings prove highly attractive for use in flexible optoelectronics.