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MicroRNAs (miRNAs) are produced from highly structured primary transcripts (pri-miRNAs) and regulate numerous biological processes in eukaryotes. Due to the extreme heterogeneity of these structures, the initial processing sites of plant pri-miRNAs and the structural rules that determine their processing have been predicted for many miRNAs but remain elusive for others. Here we used semi-active DCL1 mutants and advanced degradome-sequencing strategies to accurately identify the initial processing sites for 147 of 326 previously annotated ArabidopsismiRNAs and to illustrate their associated pri-miRNA cleavage patterns. Elucidating the in vivo RNA secondary structures of 73 pri-miRNAs revealed that about 95% of them differ from in silico predictions, and that the revised structures offer clearer interpretation of the processing sites and patterns. Finally, DCL1 partners Serrate and HYL1 could synergistically and independently impact processing patterns and in vivo RNA secondary structures of pri-miRNAs. Together, our work sheds light on the precise processing mechanisms of plant pri-miRNAs.

Progranulin (PGRN) exerts multiple functions in various inflammatory diseases. However, the role of PGRN in the pathogenesis of virus infection is unknown. Here, we demonstrated that PGRN production was up-regulated in clinical and experimental influenza, which contributed to the deleterious inflammatory response after influenza virus infection in mice. PGRN-deficient mice were protected from influenza virus-induced lung injury and mortality. Decreased mortality was associated with significantly reduced influx of neutrophils and monocytes/macrophages, release of cytokines and chemokines, and permeability of the alveolar–epithelial barrier without affecting viral clearance. Our findings suggest that PGRN exacerbates pulmonary immunopathology during influenza virus infection.

Background: In order to realize current aminoglycosides supervision in food and environment, our team improved the sensitivity and separation efficiency of the portable ITO detector, based on the technology of microchip capillary electrophoresis and contactless conductivity detection. Experiment: Parameters (the separation voltage, buffer concentration, electrodes gap, elicitation frequency, elicitation voltage) were optimized for the detection of three aminoglycosides, gentamicin, kanamycin and streptomycin and the separation of their mixture in background electrolyte consists of 2-(N-Morpholino) ethanesulfonic acid (MES) and L-Histidine (His). The enhanced method was also applied to other types of aminoglycosides. Results: Under optimal conditions, the monitoring of three types of aminoglycosides obtained such a sensitive response that the limits of detection of gentamicin sulfate, kanamycin sulfate and streptomycin sulfate were calculated as 3.1 μg/ml, 0.89 μg/ml and 0.96 μg/ml, at signal-to-noise ratio 3, respectively. In addition they got separated completely from each other only in 40 s. The results of other varieties of aminoglycosides including tobramycin sulfate and amikacin sulfate also met the standard. Conclusion: We successfully proposed here an unprecedentedly portable, miniaturized and rapid microchip capillary electrophoresis contactless conductivity detection system to realize current aminoglycosides supervision in food and environment.

Cigar line Beinhart 1000-1 has effective durable resistance to black shank (BS) and is considered one of the most resistant sources in tobacco (Nicotiana tabacumL.). To investigate the inheritance and identification of stable quantitative trait loci (QTL) for BS response, F2, BC1F2individuals and BC1F2:3lines were produced from a cross between Beinhart 1000-1 and Xiaohuangjin 1025. Two major quantitative trait loci (M-QTL) named qBS7and qBS17were repeatedly detected under different conditions. QTL qBS7was mapped to the region between PT30174 and PT60621 and explained 17.40%–25.60% of the phenotypic variance under different conditions. The other QTL qBS17in interval PT61564–PT61538 of linkage group 17 was detected in a BC1F2population in the field and in BC1F2:3in both the field and at the seedling stage, explaining 6.90% to 11.60% of the phenotypic variance. The results improve our understanding of the inheritance of resistance to BS and provide information that can be used in marker-assisted breeding.

A modified indium tin oxide (ITO) microelectrode detector integrated with a dual-channel polydimethylsiloxane (PDMS) microchip is proposed for in-channel amperometric detection in microchip electrophoresis (ME). The gold nanoparticle (GNP)-modified ITO-coated poly-ethylene terephthalate film electrode was fabricated viaa photolithography process and direct electrochemical deposition. This electrode fabrication method reduced the cost of this microchip a lot. The electroplating conditions for the GNP-modified ITO electrode were optimized through evaluating the effect on the detection sensitivity and separation efficiency of a dual-channel ME system. Under the optimal conditions, the performance of the new ME amperometric detection system has been demonstrated by analyzing a mixture of p-aminophenol, o-aminophenol and m-aminophenol, which achieved the detection limits of 0.24 μM, 0.41 μM and 0.42 μM, respectively. Finally, the successful detection of antibiotics demonstrated the potential of this dual-channel microchip system for clinical application.

Extensive genetics and genomics analyses reveal the co-transcriptional processing mode of primary substrates of microRNAs in Arabidopsis, and an unexpected promoting role of R-loops in the process.

A conducting thin film contactless conductivity detection (CCD) sensor integrated with microchip capillary electrophoresis (CE) has been developed for the detection of metal ions. The CCD sensors were patterned on an indium tin oxide (ITO) coated poly(ethylene terephthalate) (PET) film using DuPont dry film as a negative photoresist, followed by the bonding of a poly(dimethylsiloxane) plate with the opposite side of the PET film. With the introduction of low-cost ITO-coated films and photosensitive films, the efficiency of prototyping and fabricating the desired microchip CE–CCD system was significantly enhanced. Relevant experimental parameters for using CCD to analyze metal ions were optimized, which include the concentration of the run buffer, gap between the two sensing electrodes, and excitation voltage and frequency. The analytical performance of the proposed device was illustrated by the separation of potassium, sodium, and lithium ions, which achieved the detection limits of 5.8 μM, 8.0 μM, and 14.3 μM, respectively. Furthermore, the versatility of the device was demonstrated by the determination of a simulation sample with a mixture of heavy metal ions, which included zinc, cadmium, and copper ions in Xiangjiang River water. The three weak base ions were completely separated within 1 min with negative peaks because they bind with acetate ions.