This review provides an overview of development in the design, synthesis, and application of multifunctional porous hydrogen-bonded organic framework (HOF) materials.

Recently, the development of clean sustainable energy storage and conversion technologies to deal with environmental pollution and the forthcoming energy crisis has attracted much attention in the energy research community. It is critical to develop carriers to store energy or to facilitate mass and electron transportation in energy storage and conversion. The emerging metal-organic frameworks (MOFs) are well suited for this purpose because of their inherent advantages, including structural diversity, functionality, tailorability, and versatile applications. Moreover, when utilized as supports and sacrificial precursors, MOFs can immobilize active functional materials and create highly controllable nanostructures, respectively, gaining new momentum for energy applications. In this review, we present the recent progress in the field of energy storage and conversion using MOFs and their composites and derivatives by focusing on the correlation of structure, composition, and function.

Microhomology-mediated end joining (MMEJ) is a major pathway for Ku-independent alternative nonhomologous end joining, which contributes to chromosomal translocations and telomere fusions, but the underlying mechanism of MMEJ in mammalian cells is not well understood. In this study, we demonstrated that, distinct from Ku-dependent classical nonhomologous end joining, MMEJ-even with very limited end resection-requires cyclin-dependent kinase activities and increases significantly when cells enter S phase. We also showed that MMEJ shares the initial end resection step with homologous recombination (HR) by requiring meiotic recombination 11 homolog A (Mre11) nuclease activity, which is needed for subsequent recruitment of Bloom syndrome protein (BLM) and exonuclease 1 (Exo1) to DNA double-strand breaks (DSBs) to promote extended end resection and HR. MMEJ does not require S139-phosphorylated histone H2AX (γ-H2AX), suggesting that initial end resection likely occurs at DSB ends. Using a MMEJ and HR competition repair substrate, we demonstrated that MMEJ with short end resection is used in mammalian cells at the level of 10-20% of HR when both HR and nonhomologous end joining are available. Furthermore, MMEJ is used to repair DSBs generated at collapsed replication forks. These studies suggest that MMEJ not only is a backup repair pathway in mammalian cells, but also has important physiological roles in repairing DSBs to maintain cell viability, especially under genomic stress.BLM/Exo1 | CtIP | DNA repair pathway | DNA damage | genome stability D NA double-strand breaks (DSBs) can be repaired by multiple pathways. The classical nonhomologous end joining (C-NHEJ) pathway relies on Ku70/Ku80 and ligates DSB ends without a template (1). Homologous recombination (HR), an error-free pathway, uses a homologous template to repair DSBs (2) and is initiated by end resection from DSB ends to generate a long stretch of singlestrand DNA (ssDNA) for strand invasion. Although C-NHEJ is active throughout the cell cycle, HR is used when cells enter S and G2 because cyclin-dependent kinases (CDKs) are needed for promoting end resection to activate HR (3-5).In the absence of C-NHEJ factors such as Ku70, Ku80, or DNA ligase IV, robust alternative nonhomologous end joining (alt-NHEJ) activity is observed in various organisms including yeast and mammals (6, 7). Many alt-NHEJ events, classified as microhomology-mediated end joining (MMEJ), require end resection and join the ends by base pairing at microhomology sequences (5-25 nucleotides), resulting in deletions at the junctions (6). However, other alt-NHEJ pathways without using microhomology regions also exist.Genetic analyses in yeast reveal that MMEJ is Rad52-independent, distinguishing it from HR and single-strand annealing (SSA) repair pathways, whereas the Mre11-Rad50-Xrs2 (MRX) complex and DNA ligase IV are needed for MMEJ (8-10). Further studies suggest that in yeast, Srs2 helicase, Sae2 nuclease [CtBP-interacting protein (CtIP) homologue], Tel1 [ataxia telangiectasia mutated (A...

Functional analysis of genome sequences requires methods for cloning DNA of interest. However, existing methods, such as library cloning and screening, are too demanding or inefficient for high-throughput application to the wealth of genomic data being delivered by massively parallel sequencing. Here we describe direct DNA cloning based on the discovery that the full-length Rac prophage protein RecE and its partner RecT mediate highly efficient linear-linear homologous recombination mechanistically distinct from conventional recombineering mediated by Redαβ from lambda phage or truncated versions of RecET. We directly cloned all ten megasynthetase gene clusters (each 10–52 kb in length) from Photorhabdus luminescens into expression vectors and expressed two of them in a heterologous host to identify the metabolites luminmycin A and luminmide A/B. We also directly cloned cDNAs and exactly defined segments from bacterial artificial chromosomes. Direct cloning with full-length RecE expands the DNA engineering toolbox and will facilitate bioprospecting for natural products.

Wild relatives of crops are an important source of genetic diversity for agriculture, but their gene repertoire remains largely unexplored. We report the establishment and analysis of a pan-genome of Glycine soja, the wild relative of cultivated soybean Glycine max, by sequencing and de novo assembly of seven phylogenetically and geographically representative accessions. Intergenomic comparisons identified lineage-specific genes and genes with copy number variation or large-effect mutations, some of which show evidence of positive selection and may contribute to variation of agronomic traits such as biotic resistance, seed composition, flowering and maturity time, organ size and final biomass. Approximately 80% of the pan-genome was present in all seven accessions (core), whereas the rest was dispensable and exhibited greater variation than the core genome, perhaps reflecting a role in adaptation to diverse environments. This work will facilitate the harnessing of untapped genetic diversity from wild soybean for enhancement of elite cultivars.

Background Ferroptosis is a novel mode of non-apoptotic cell death induced by build-up of toxic lipid peroxides (lipid-ROS) in an iron dependent manner. Cancer-associated fibroblasts (CAFs) support tumor progression and drug resistance by secreting various bioactive substances, including exosomes. Yet, the role of CAFs in regulating lipid metabolism as well as ferroptosis of cancer cells is still unexplored and remains enigmatic. Methods Ferroptosis-related genes in gastric cancer (GC) were screened by using mass spectrum; exosomes were isolated by ultra-centrifugation and CAF secreted miRNAs were determined by RT-qPCR. Erastin was used to induce ferroptosis, and ferroptosis levels were evaluated by measuring lipid-ROS, cell viability and mitochondrial membrane potential. Results Here, we provide clinical evidence to show that arachidonate lipoxygenase 15 (ALOX15) is closely related with lipid-ROS production in gastric cancer, and that exosome-miR-522 serves as a potential inhibitor of ALOX15. By using primary stromal cells and cancer cells, we prove that exosome-miR-522 is mainly derived from CAFs in tumor microenvironment. Moreover, heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) was found to mediate miR-522 packing into exosomes, and ubiquitin-specific protease 7 (USP7) stabilizes hnRNPA1 through de-ubiquitination. Importantly, cisplatin and paclitaxel promote miR-522 secretion from CAFs by activating USP7/hnRNPA1 axis, leading to ALOX15 suppression and decreased lipid-ROS accumulation in cancer cells, and ultimately result in decreased chemo-sensitivity. Conclusions The present study demonstrates that CAFs secrete exosomal miR-522 to inhibit ferroptosis in cancer cells by targeting ALOX15 and blocking lipid-ROS accumulation. The intercellular pathway, comprising USP7, hnRNPA1, exo-miR-522 and ALOX15, reveals new mechanism of acquired chemo-resistance in GC. Graphical abstract

We observe highly efficient dynamic spin injection from Y 3 Fe 5 O 12 (YIG) into NiO, an antiferromagnetic (AF) insulator, via strong coupling, and robust spin propagation in NiO up to 100-nm thickness mediated by its AF spin correlations. Strikingly, the insertion of a thin NiO layer between YIG and Pt significantly enhances the spin currents driven into Pt, suggesting exceptionally high spin transfer efficiency at both YIG/NiO and NiO/Pt interfaces. This offers a powerful platform for studying AF spin pumping and AF dynamics as well as for exploration of spin manipulation in tailored structures comprising metallic and insulating ferromagnets, antiferromagnets and nonmagnetic materials.

Cells can sense and respond to mechanical signals over relatively long distances across fibrous extracellular matrices. Recently proposed models suggest that long-range force transmission can be attributed to the nonlinear elasticity or fibrous nature of collagen matrices, yet the mechanism whereby fibers align remains unknown. Moreover, cell shape and anisotropy of cellular contraction are not considered in existing models, although recent experiments have shown that they play crucial roles. Here, we explore all of the key factors that influence long-range force transmission in cell-populated collagen matrices: alignment of collagen fibers, responses to applied force, strain stiffening properties of the aligned fibers, aspect ratios of the cells, and the polarization of cellular contraction. A constitutive law accounting for mechanically driven collagen fiber reorientation is proposed. We systematically investigate the range of collagen-fiber alignment using both finite-element simulations and analytical calculations. Our results show that tension-driven collagen-fiber alignment plays a crucial role in force transmission. Small critical stretch for fiber alignment, large fiber stiffness and fiber strain-hardening behavior enable long-range interaction. Furthermore, the range of collagen-fiber alignment for elliptical cells with polarized contraction is much larger than that for spherical cells with diagonal contraction. A phase diagram showing the range of force transmission as a function of cell shape and polarization and matrix properties is presented. Our results are in good agreement with recent experiments, and highlight the factors that influence long-range force transmission, in particular tension-driven alignment of fibers. Our work has important relevance to biological processes including development, cancer metastasis, and wound healing, suggesting conditions whereby cells communicate over long distances.