In recent years, the United States Food and Drug Administration (US FDA) has documented several instances where more abundant, and lower priced, jumbo squid (Dosidicus gigas) has been substituted for octopus (family Octopodidae) in a variety of products (e.g. frozen, canned) resulting in the products being misbranded and/or adulterated. FDA typically utilises a short (approx. 655 base pair) fragment of the cytochrome c oxidase subunit 1 (COI) mitochondrial gene (a.k.a. DNA barcoding) for the identification of seafood products. However, this method is not applicable for the identification of canned products due to DNA fragmentation that occurs during the retort process. Described herein is a modified DNA barcoding method using standard DNA marine invertebrate barcoding primers in combination with degenerate forward and reverse internal primers to create two smaller (313-316 base pair) fragments. The fragments are sequenced separately then assembled to form a nearly full-length DNA barcode fragment. Using this method, 11 of the 12 canned jumbo squid and octopus products tested, in a variety of forms (i.e. in hot sauce, in garlic sauce, smoked, etc.), were successfully identified. This method is fit for the purpose of ad hoc regulatory identification of canned squid and octopus products to confirm product labelling or to be used as a screening tool to prevent species substitution, economic adulteration, and fraud.

Group 13 and related fillers are cornerstone components for advanced composites, yet their severe interfacial incompatibility with organic matrices inherently limits their practical efficacy. Conventional surface modification strategies remain fundamentally constrained by a heavy reliance on hazardous solvents, matrix curing inhibition, and structural degradation of the fillers. Herein, we report a solvent-free mechanochemical copolymerization strategy that establishes an universal, non-destructive interfacial engineering paradigm for diverse Group 13 and related fillers (nano-Al, B4C, and ZrB2). By directly architecting sulfur-containing polymer coatings on filler surfaces, this approach elegantly exploits intrinsic Lewis acid-base pairing between electron-deficient metal/metalloid sites and electron-rich sulfur moieties. Mechanistically, the resulting electronic configurations and coordination chemistry are systematically elucidated via a synergistic combination of XPS, solid-state [11]B NMR, and DFT calculations, confirming the formation of robust S-Al and S-B coordinative networks. The extraordinary universality of this matrix-agnostic platform is validated by incredible performance increments across three distinct frontiers, driving a staggering 666% surge in combustion enthalpy for nano-Al fuels, a 33% ablation reduction for ZrB2 thermal shields, and concurrent ∼270% elevations in both strength and toughness for B4C structural composites. Ultimately, this environmentally benign protocol paves a versatile avenue toward the green synthesis of high-performance hybrids.

Type 1 diabetes (T1D) is a complex autoimmune disease characterized by the destruction of insulin-producing pancreatic β cells. Both genetic susceptibility and epigenetic dysregulation contribute to T1D risk. Recent studies have reported β-cell dysfunction before disease onset, suggesting that β-cell-intrinsic mechanisms contribute to pathogenesis. However, the mechanistic link between disease-associated variants and β-cell dysfunction remains poorly understood. We hypothesized that a subset of T1D-associated variants directly influences cell type-specific candidate cis-regulatory elements (cCREs) by disrupting transcription factor (TF) binding and altering gene expression. To define cell type-specific cCREs in human islets, we integrated publicly available epigenomic datasets, including bulk histone modification profiles and single-cell multiomic data from human pancreatic islets. We combined these data with T1D genome-wide association study (GWAS) variants to identify disease-associated SNPs located within enhancer regions. Using multiomic datasets from PANC-DB, we characterized cell type-specific chromatin accessibility in nondiabetic and T1D islets and identified regulatory regions that may control gene expression in β cells and other islet cell types. We then applied ChromBPNet, a deep learning model that predicts base-pair-resolution chromatin accessibility from scATAC-seq data, to evaluate how specific variants may alter local regulatory activity. In parallel, we used TF footprinting to nominate TFs likely to bind these variant-containing regions. These analyses identified several T1D-associated SNPs predicted to alter chromatin accessibility at candidate TF binding sites, suggesting mechanisms by which noncoding variants may contribute to β-cell dysfunction and T1D susceptibility. Our findings link T1D-associated variants to cell type-specific enhancer activity and regulatory pathways and provide candidates for future mechanistic studies.

A series of N-heterocyclic carbene (NHC)-stabilized phosphanylgallanes and highly temperature sensitive phosphanylalanes bearing aliphatic and aromatic substituents at the phosphorus atom were synthesized via salt metathesis reactions of IDipp-coordinated (IDipp = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene) triel halide precursors with alkali metal phosphanides. The gallium derivatives IDipp∙GaH2PH[t]Bu (1) and IDipp∙GaH2P([t]Bu)2 (2) were isolated and structurally characterized, revealing monomeric species with distorted tetrahedral coordination at the group 13 element. The corresponding aluminum compounds IDipp·AlEt2PHtBu (3), IDipp·AlEt2PHPh (4), IDipp·AlEt2PPh2 (5), and IDipp·AlEt2PH2 (6) exhibit a strong dependence of their electronic and structural properties on the substitution pattern at the phosphorus atoms. X-ray diffraction studies show that Al─P bonds in the P atom substituted phosphanylalanes are elongated compared to IDipp·AlEt2PH2. Furthermore, computational analysis of the frontier molecular orbitals revealed the availability of the phosphorus lone pair. Comparison of donor abilities of the studied compounds with known substituted phosphanylboranes also indicates that these phosphanylalanes and -gallanes can serve as strong σ donating ligands. The reactivity of phosphanylgallanes toward SMe2·BH3 with formation of IDipp·GaH2PPh2·BH3 (9) and IDipp·GaH2PH2·BH3 (10), respectively, confirms the accessibility of the phosphorus lone pair and highlights their potential as Lewis base compounds.

Investigation of the interactions of methane with metal oxides is crucial for elucidating absorption configurations at active sites of catalysts, which has proven to be a challenging experimental target due to the difficulty in size selection of neutral systems. In this work, the interactions of methane with rare earth metal oxides are studied by using size-specific infrared-vacuum ultraviolet spectroscopy and quantum chemical calculations. Two distinct configurations of methane adsorption are found in the MO(CH4)n (M = Ce, Y; n = 1-3) complexes. In the first configuration, the C and H atoms of methane are positioned between a Lewis acid-base pair (M2+-O2-); in the second configuration, one H atom of methane is oriented toward a Lewis basic oxygen anion (O2-). Such adsorption features of methane on cerium and yttrium monoxides are dominantly governed by electrostatic interactions. These findings provide key microscopic information for methane adsorption on metal oxides that are helpful for understanding the crucial initial steps in the catalytic cycles.

Riboswitches are non-coding RNA sequences that control cellular processes through ligand binding. Conformational heterogeneity is fundamental to riboswitch functionality, yet this same attribute makes structural characterization of these mRNA elements challenging. Here, we use cryo-electron microscopy to characterize different structural populations of the glycine riboswitch tandem aptamers, and molecular dynamics simulations to support the observed ligand orientation in the holo state. We find that Mg2+ enables formation of the fully folded "walking man" conformation, which consists of a rigidified core and two dynamic helices, but is insufficient on its own to make this the dominant state. In Mg²⁺ conditions alone, approximately one-third of the picked particles are fully folded, whereas two thirds adopt distinct, partially folded states. Glycine interactions further stabilize the fully folded conformation, doubling the relative population of fully folded particles by stabilizing a conserved inter-aptamer Hoogsteen base pair, enabling our capture of a 2.9 Å-resolution structure for this RNA-only system. The population data show that glycine and Mg²⁺ operate synergistically: glycine enhances Mg²⁺ localization, while Mg2+ drives glycine recruitment. Our findings indicate that cryo-electron microscopy offers a promising avenue to characterize RNA folding ensembles.

G-quadruplexes (G4s) are non-canonical DNA structures enriched in gene promoters and involved in transcriptional regulation, making them attractive drug targets, albeit difficult to target individually with high specificity due to their structural similarity. In the human c-KIT promoter, three adjacent G4 motifs (c-KIT1, c-KIT*, and c-KIT2) modulate oncogene expression, yet their individual contributions remain poorly understood, posing a significant challenge for selective targeting and underscoring the need for tools capable of discriminating between closely spaced G4s. Here, we report a dual-recognition strategy that combines the sequence specificity of peptide nucleic acids (PNAs) with the stabilizing properties of a G4 ligand to achieve site-selective and programmable targeting of neighboring G4s. Sequence-specific base pairing enables the PNA probe to recognize the flanking region between the c-KIT1 and c-KIT* motifs, positioning the ligand in proximity to a defined G4 structure and enabling directional and selective stabilization. Ligand conjugation at the N- or C-terminus of the PNA directs selective targeting of individual G4 units, while dual conjugation enables their simultaneous stabilization. This approach provides positional control not accessible with conventional small-molecule ligands and establishes a modular platform for targeting G4s within regions containing closely spaced motifs. A dual luciferase assay revealed that targeted G4 stabilization within the c-KIT promoter leads to distinct transcriptional outcomes in cells, indicating distinct regulatory roles of the c-KIT1 and c-KIT* motifs. This PNA-ligand platform enables site-specific recognition and discrimination between adjacent G4s and provides a general framework for selective chemical intervention in G4-regulated oncogenes.

Alpha-thalassemia/mental retardation syndrome X-linked protein (ATRX) is an ATP-dependent chromatin remodeler that performs diverse functions. The mechanism by which ATRX modulates chromatin is unknown. Here, our cryo-electron microscopy (cryo-EM) structure revealed that human ATRX recognizes the nucleosome through its C-terminal regions by embracing and unwrapping ∼18 base pair nucleosomal DNA near entry/exit sites in the presence of ADP⋅BeF3. Strikingly, the DNA minor groove between super helical location (SHL)6 and SHL7 is profoundly deformed by a "pin-like" structure on the "poking helix" in ATRX, which intercalates the aromatic side chain of a phenylalanine into the base stacking. To translocate the DNA on the nucleosome, ATRX further utilizes a disordered insertion to contact the histone surface and a positively charged loop to bridge cross-gyre interactions. Both the "pin-like" structure and the histone-contacting region of ATRX were found to be essential for protecting cells from G-quadruplex DNA-induced stress, highlighting the importance of these features in ATRX-mediated chromatin remodeling.

Porphycenes as constitutional isomers of porphyrins require more demanding synthesis but exhibit fascinating and useful properties. In free-base porphycenes, tautomerism in the ground state and strong fluorescence from the photoexcited singlet state are established. Production of reactive oxygen species (ROS) via the photoexcited triplet state is observed for both free-base and metalloporphycenes. These aspects have been extensively studied, whereas the properties of the photoexcited triplet states remain underexplored. Here, we present an improved synthetic protocol and characterization of 2,7,12,17-tetra-tert-butyl porphycene and its Pd[2+] complex. We characterize the ground states of both compounds with cyclic voltammetry and UV/VIS spectroscopy, and use transient EPR (trEPR) spectroscopy to investigate their photoexcited triplet states. For free-base porphycenes, tautomerization effects are observed via temperature-dependent trEPR measurements, whereas these are absent in the Pd[2+] complex. The zero-field splitting (ZFS) parameters demonstrate that the Pd[2+] complex retained its π-π* character. In contrast, a reorientation of spin polarization from in-plane in the free-base compound to out-of-plane in the Pd[2+] complex is observed. The experimental data are complemented by DFT and CASSCF calculations. These results provide a basis for selective modification of the porphycene macrocycle to control its triplet properties. These findings are relevant to applications such as photodynamic therapy (PDT) and spin polarization transfer via the radical triplet pair mechanism (RTPM).

Orthogonal DNA replication system-based continuous evolution enables user-defined genes to undergo a hypermutagenic evolutionary state through a replication process independent of the host genome, while maintaining overall cellular stability. However, its application is constrained by the relatively low mutation rate of orthogonal error-prone DNA polymerases (ep-DNAP) and by strong mutation bias during misincorporation. To address this, we developed nucleoside deaminase-assisted orthogonal DNA replication (NDAORep) systems, in which nucleoside deaminases (NDA) are coupled to orthogonal DNA replication to enhance and tune mutagenesis. NDAORep was implemented in engineered Bacillus thuringiensis and synthetic Escherichia coli systems, achieving mutation rates up to 1.16 × 10[-4] substitutions per base pair per generation (s.p.b.), approximately 880,000-fold to the host genome with adjustable mutation bias. Using NDAORep, we rapidly evolved a strong constitutive P43 promoter to a variant with 6.88-fold higher activity after only 12 h, compared with 8 days using ep-DNAP alone. We also evolved more efficient orthogonal aminoacyl-tRNA synthetases (aaRSs) in B. thuringiensis and E. coli, enhancing p-azido-L-phenylalanine incorporation by up to 50% and 83%, respectively. Furthermore, NDAORep enabled optimization of a synthetic formate assimilation pathway in E. coli, increasing formate assimilation 5-fold. Collectively, these results demonstrate that NDAORep accelerates the evolution of regulatory elements, protein functions, and metabolic pathways, establishing a powerful platform for metabolic engineering and synthetic biology. By coupling programmable mutational diversity with continuous selection, NDAORep enables rapid optimization of complex biological systems that are difficult to engineer through conventional approaches.

Ultrasensitive and field-deployable detection of Pb[2+] is highly desirable for environmental monitoring and public health protection. Nucleic acid-based sensors are promising for this purpose because they are programmable and compatible with isothermal analysis. However, current amplification strategies face a fundamental trade-off: enzyme-assisted methods provide high sensitivity yet require unstable protein catalysts and cold-chain logistics, whereas enzyme-free circuits are operationally robust but suffer from thermodynamic background leakage. To address this sensitivity-stability paradox, we propose PADLOCK (Pb[2+]-Activated Dual-DNAzyme Locked On-site Cascade Kit), a protein-enzyme-free amplification strategy operating at ambient temperature (25 °C). PADLOCK uses a two-stage catalytic cascade for high-gain signal amplification. Specifically, the upstream GR-5 DNAzyme module was optimized by tuning hairpin stem complementarity and loop geometry to suppress premature trigger release, while the downstream self-locked DNAzyme (SLD) was redesigned through base-pair engineering to improve the signal-to-noise ratio. This cascaded "cleavage-then-unlock" architecture achieves amplification gains substantially exceeding those of conventional enzyme-free circuits such as catalytic hairpin assembly (CHA) or hybridization chain reaction (HCR), while maintaining near-zero background, a combination that is difficult to achieve in enzyme-free systems. Under optimal conditions, PADLOCK demonstrates a sensitivity range of 1 pM to 1 μM with a detection limit of 342 fM and exceptional selectivity over eight competing ions. Reliable quantification in real water and soil samples yielded spike recoveries of 98.17%-111.69%. Furthermore, integration with a custom-built smartphone imaging interface further enables visual monitoring across 100 pM-1 μM, providing a robust, point-of-care testing (POCT) platform that eliminates cold-chain logistics and enables ambient-temperature operation for decentralized heavy-metal screening in resource-limited settings.

Chang, F, Zhang, Y, Qian, D, Liu, T, and Marshall, P. Increasing robotic horizontal resistance alters pair-specific intermuscular timing during sprint acceleration. J Strength Cond Res XX(X): 000-000, 2026-The purpose of this study was to determine whether increasing horizontal resistance alters pair-specific intermuscular timing and coupling during sprint acceleration. Fifteen university sprinters, 8 men and 7 women, performed maximal 30-m accelerations under 4 randomized robotic horizontal resistance conditions of 0, 5, 10, and 15% body weight (BW). Surface electromyography (EMG) was recorded from gluteus maximus (GMax), biceps femoris (BF), and gastrocnemius medialis (GM). All EMG channels shared a common acquisition time base. Gluteus maximus onset was used to define a common 300-ms analysis window, and normalized cross-correlation quantified temporal lag at peak correlation and coupling strength for the GMax-BF and GMax-GM pairs within a fixed ±100-ms lag range. Increasing resistance produced a greater GMax-GM lag at 15% than at 0% BW (paired mean difference 29.6 ms, 95% confidence interval: 14.1-45.1 ms; Holm-adjusted p = 0.006; Hedges' g = 0.90). No corrected GMax-BF pairwise contrast was identified, and coupling strength was unaffected by load in either muscle pair. For practitioners, resisted-sprint load selection may therefore influence the acute intermuscular timing demands imposed during acceleration, although the present results do not identify an optimal load or establish transfer to unresisted sprint performance.