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Transcriptome-wide identification of RNA-binding proteins (RBPs) is a prerequisite for understanding the posttranscriptional gene regulation networks. However, proteomic profiling of RBPs has been mostly limited to polyadenylated mRNA-binding proteins, leaving RBPs on nonpoly(A) RNAs, including most noncoding RNAs (ncRNAs) and pre-mRNAs, largely undiscovered. Here we present a click chemistry-assisted RNA interactome capture (CARIC) strategy, which enables unbiased identification of RBPs, independent of the polyadenylation state of RNAs. CARIC combines metabolic labeling of RNAs with an alkynyl uridine analog and in vivo RNA-protein photocross-linking, followed by click reaction with azide-biotin, affinity enrichment, and proteomic analysis. Applying CARIC, we identified 597 RBPs in HeLa cells, including 130 previously unknown RBPs. These newly discovered RBPs can likely bind ncRNAs, thus uncovering potential involvement of ncRNAs in processes previously unknown to be ncRNA-related, such as proteasome function and intermediary metabolism. The CARIC strategy should be broadly applicable across various organisms to complete the census of RBPs.

Cancers and developmental disorders are associated with alterations in the 3D genome architecture in space and time (the fourth dimension). Mammalian 3D genome organization is complex and dynamic and plays an essential role in regulating gene expression and cellular function. To study the causal relationship between genome function and its spatio-temporal organization in the nucleus, new technologies for engineering and manipulating the 3D organization of the genome have been developed. In particular, CRISPR–Cas technologies allow programmable manipulation at specific genomic loci, enabling unparalleled opportunities in this emerging field of 3D genome engineering. We review advances in mammalian 3D genome engineering with a focus on recent manipulative technologies using CRISPR–Cas and related technologies.There is a rapidly growing appreciation of the complexities of 3D genome organization, as well as associations with gene expression and wider cellular and organismal phenotypes, including diseases. In this Review, the authors describe diverse experimental methods for manipulating 3D genome organization — from fine-scale control of DNA contacts to large-scale nuclear repositioning — which are facilitating detailed testing of the biological functions of 3D genome organization.

The SARS-CoV-2 viral infection transforms host cells and produces special organelles in many ways, and we focus on the replication organelles, the sites of replication of viral genomic RNA (vgRNA). To date, the precise cellular localization of key RNA molecules and replication intermediates has been elusive in electron microscopy studies. We use super-resolution fluorescence microscopy and specific labeling to reveal the nanoscopic organization of replication organelles that contain numerous vgRNA molecules along with the replication enzymes and clusters of viral double-stranded RNA (dsRNA). We show that the replication organelles are organized differently at early and late stages of infection. Surprisingly, vgRNA accumulates into distinct globular clusters in the cytoplasmic perinuclear region, which grow and accommodate more vgRNA molecules as infection time increases. The localization of endoplasmic reticulum (ER) markers and nsp3 (a component of the double-membrane vesicle, DMV) at the periphery of the vgRNA clusters suggests that replication organelles are encapsulated into DMVs, which have membranes derived from the host ER. These organelles merge into larger vesicle packets as infection advances. Precise co-imaging of the nanoscale cellular organization of vgRNA, dsRNA, and viral proteins in replication organelles of SARS-CoV-2 may inform therapeutic approaches that target viral replication and associated processes. The precise cellular localization of the SARS-CoV-2 RNA and replication partners has been elusive. Here, the authors use super-resolution fluorescence microscopy and specific labeling to reveal the nanoscale structure of viral replication organelles.

Xanthoceras sorbifolium Bunge leaves (XBL), traditionally consumed as herbal tea, have attracted increasing attention as potential functional food ingredients for managing type 2 diabetes mellitus (T2DM). This study investigated the anti-diabetic effects of an aqueous XBL extract in T2DM rats induced with a high-fat, high-sucrose diet combined with streptozotocin. XBL administration significantly improved glycemic control, insulin sensitivity, lipid profiles, and pancreatic and renal histopathology. Integrated 16S rRNA sequencing and untargeted fecal metabolomics revealed the modulation of key metabolic pathways, including linoleic acid and histidine metabolism, and elevated production of short-chain fatty acids (SCFAs) such as acetate and propionate. XBL also enriched beneficial gut microbes including Prevotella, Lachnospiraceae_NK4A136_group, and [Eubacterium]_xylanophilum_group, whose abundance showed positive correlations with SCFA levels and metabolic improvements. These findings demonstrate that XBL ameliorates T2DM through gut microbiota–SCFA–metabolite interactions and suggest its potential as a natural, multi-target dietary strategy for metabolic health management.

A major challenge in coronavirus vaccination and treatment is to counteract rapid viral evolution and mutations. Here we demonstrate that CRISPR-Cas13d offers a broad-spectrum antiviral (BSA) to inhibit many SARS-CoV-2 variants and diverse human coronavirus strains with >99% reduction of the viral titer. We show that Cas13d-mediated coronavirus inhibition is dependent on the crRNA cellular spatial colocalization with Cas13d and target viral RNA. Cas13d can significantly enhance the therapeutic effects of diverse small molecule drugs against coronaviruses for prophylaxis or treatment purposes, and the best combination reduced viral titer by over four orders of magnitude. Using lipid nanoparticle-mediated RNA delivery, we demonstrate that the Cas13d system can effectively treat infection from multiple variants of coronavirus, including Omicron SARS-CoV-2, in human primary airway epithelium air-liquid interface (ALI) cultures. Our study establishes CRISPR-Cas13 as a BSA which is highly complementary to existing vaccination and antiviral treatment strategies. A major challenge in coronavirus vaccination and treatment is to counteract rapid viral evolution and mutations. Here the authors show that CRISPR-Cas13d can be used as a broad-spectrum antiviral to inhibit human coronaviruses, including new SARS-CoV-2 variants, combined with small molecule drugs for an enhanced antiviral effect in human primary cells.

Characterization of selenium states by 77 Se NMR is quite important to provide vital information for mechanism studies in organoselenium-catalyzed reactions. With the development of heterogeneous polymer-supported organoselenium catalysts, the solid state 77 Se NMR comes to the spotlight. It is necessary to figure out an advanced protocol that provides good quality spectra within limited time because solid state 77 Se NMR measurements are always time consuming due to the long relaxation time and the relatively low sensitivity. Studies on small molecules and several novel polymer-supported organoselenium materials in this article showed that cross polarization (CP) method with the assistance of magic angle spinning (MAS) was more efficient to get high quality spectra than the methods by using single pulse (SP) or high power 1 H decoupling (HPHD) combined with MAS. These results lead to a good understanding of the effect of the molecular structure, the heteronuclear coupling, the long-range ordering of the solid (crystal or amorphous), and the symmetry of 77 Se on quality of their spectra.

In recent years, building fires have become more frequent, leading to significant degradation of concrete’s mechanical properties after fire exposure. This reduction in strength affects the structural performance and load‐bearing capacity of concrete, posing serious risks to building safety. Therefore, studying the failure characteristics and constitutive models of concrete after fire exposure is crucial. In order to investigate coupling effect of temperature and constant temperature duration on the fracture mode of concrete, this article employs methods such as experiments, theoretical analysis, and numerical simulation to analyze the fracture characteristics and constitutive model of concrete under the conditions of 20–800°C and constant temperature for 1 and 2 h, aiming to break through the limitation that traditional studies only focus on the single factor of temperature. The results reveal that as the fire temperature and holding time increase, the physical properties of concrete change significantly. The mass loss rate gradually increases, and the concrete color changes from gray (200°C) to light yellow (400°C), yellow‐white (600°C), and reddish‐brown (800°C). As the temperature rises, the stress–strain curve flattens, the slope decreases, the compaction phase becomes more pronounced, the peak strain increases, and the peak point shifts downward and to the right, indicating a transition from brittle to ductile behavior. Additionally, as the temperature increases, the failure rate slows down, and the number of cracks increases. Cracks predominantly form in the bonded fine aggregate regions, and when encountering larger particles, they tend to propagate along the interfaces of these particles, with less damage occurring to the larger particles themselves. A statistical damage constitutive model based on the Weibull distribution function was established. The theoretical curves closely match the experimental data, effectively capturing the various mechanical behaviors of concrete after high‐temperature exposure, including brittleness, plasticity, and strain softening, thereby validating the model’s applicability. As temperature increases, thermal stresses induce internal damage in the concrete, leading to a rise in tensile‐shear failure between particles. Moreover, at the same temperature, an increase in holding time results in a significant reduction in concrete strength and deformation resistance, highlighting the time effect. These findings offer a theoretical foundation for assessing and repairing concrete components after fire exposure and contribute to advancing the theory of fire‐resistant design for concrete structures.

Colorectal carcinoma (CRC) is one of the most common types of digestive cancer. It has been reported that the ectopic expression of microRNAs (miRs) plays a critical role in the occurrence and progression of CRC. In addition, it has also been suggested that miR-151a-5p may serve as a useful biomarker for the early detection and treatment of different types of cancer and particularly CRC. However, the specific effects and underlying mechanisms of miR-151a-5p in CRC remain elusive. The results of the current study demonstrated that miR-151a-5p was upregulated in CRC cell lines and clinical tissues derived from patients with CRC. Functionally, the results showed that miR-151a-5p significantly promoted CRC cell proliferation, migration and invasion. Additionally, dual luciferase reporter assays verified that agmatinase (AGMAT) was a direct target of miR-151a-5p and it was positively associated with miR-151a-5p expression. Mechanistically, miR-151a-5p could enhance the epithelial-mesenchymal transition of CRC cells. Taken together, the results of the current study revealed a novel molecular mechanism indicating that the miR-151a-5p/AGMAT axis could serve a crucial role in the regulation of CRC and could therefore be considered as a potential therapeutic strategy for CRC.

Cheap, abundant but seldom-employed Ca(OH) 2 was found to be an excellent low-loading (5–10 mol%) catalyst for Claisen-Schmidt condensation of aldehydes with methyl ketones under mild conditions. It was interesting that dilute aqueous ethanol (20 v/v%) was unexpectedly discovered to be the optimal solvent. The reaction was scalable at least to 100 mmol and calcium could be precipitated by CO 2 and removed by filtration. Evaporation of solvent directly afforded the product in the excellent 96% yield with high purity, as confirmed by its 1 H NMR spectrum.

Characterization of selenium states by Se NMR is quite important to provide vital information for mechanism studies in organoselenium-catalyzed reactions. With the development of heterogeneous polymer-supported organoselenium catalysts, the solid state Se NMR comes to the spotlight. It is necessary to figure out an advanced protocol that provides good quality spectra within limited time because solid state Se NMR measurements are always time consuming due to the long relaxation time and the relatively low sensitivity. Studies on small molecules and several novel polymer-supported organoselenium materials in this article showed that cross polarization (CP) method with the assistance of magic angle spinning (MAS) was more efficient to get high quality spectra than the methods by using single pulse (SP) or high power H decoupling (HPHD) combined with MAS. These results lead to a good understanding of the effect of the molecular structure, the heteronuclear coupling, the long-range ordering of the solid (crystal or amorphous), and the symmetry of Se on quality of their spectra.