Structural and biochemical insights into small RNA 3' end trimming by Arabidopsis SDN1.

A family of DEDDh 3'→5' exonucleases known as Small RNA Degrading Nucleases (SDNs) initiates the turnover of ARGONAUTE1 (AGO1)-bound microRNAs in Arabidopsis by trimming their 3' ends. Here, we report the crystal structure of Arabidopsis SDN1 (residues 2-300) in complex with a 9 nucleotide single-stranded RNA substrate, revealing that the DEDDh domain forms rigid interactions with the N-terminal domain and binds 4 nucleotides from the 3' end of the RNA via its catalytic pocket. Structural and biochemical results suggest that the SDN1 C-terminal domain adopts an RNA Recognition Motif (RRM) fold and is critical for substrate binding and enzymatic processivity of SDN1. In addition, SDN1 interacts with the AGO1 PAZ domain in an RNA-independent manner in vitro, enabling it to act on AGO1-bound microRNAs. These extensive structural and biochemical studies may shed light on a common 3' end trimming mechanism for 3'→5' exonucleases in the metabolism of small non-coding RNAs

The Leighton Chajnantor Telescope: Project update and mechanical structural analysis in preparations for new deployment in Chajnantor, Chile

The LCT project aims to refurbish the CSO telescope, move it from Maunakea to Chajnantor, in Chile, and operate it scientifically for 10 years. The relocation of the telescope involves a variety of changes in the working conditions, which demands in-depth mechanical analysis. To conduct the required studies, an FEM model of the entire telescope has been developed, together with CFD tools. This paper introduces the LCT project, presents the full-FEM model, its validation, and the first steps towards these analyses. Preliminary results of the simulations of the telescope, considering the working conditions at the Plateau, are also shown

PsRPs26, a 40S Ribosomal Protein Subunit, Regulates the Growth and Pathogenicity of Puccinia striiformis f. sp. Tritici

Eukaryotic ribosomes are essential for proliferation, differentiation, and cell growth. RPs26 is a ribosomal subunit structural protein involved in the growth and development process. Little is known about the function of PsRPs26 in pathogenic fungi. In this study, we isolated the RPs26 gene, PsRPs26, from Puccinia striiformis f. sp. tritici (Pst). PsRPs26 contains a eukaryotic-specific Y62–K70 motif and is more than 90% identical with its ortholog gene in other fungi. PsRPs26 was found to be localized in both the nucleus and cytoplasm. Expression of PsRPs26 increased when wheat seedlings were inoculated with the Pst CYR31 isolate. Moreover, knockdown of PsRPs26 by a host-induced gene silencing system inhibited growth and limited urediospore production in Pst. Our discovery that PsRPs26 may contribute to the pathogenicity of Pst and open a new way in the pathogenic function of PsRPs26 in cereal rust fungi

Identification of Puccinia striiformis races from the spring wheat crop in Xinjiang, China

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a foliar disease that affects both winter and spring wheat crops in Xinjiang, China, which is linked to Central Asia. Race identification of Pst from spring wheat in Xinjiang was not done before. In this study, a total of 216 isolates were recovered from stripe rust samples of spring wheat in the region in 2021 and multiplied using the susceptible cultivar Mingxian 169. These isolates were tested on the Chinese set of 19 wheat differential lines for identifying Pst races. A total of 46 races were identified. Races Suwon-11-1, Suwon11-12, and CYR32 had high frequencies in the spring wheat region. The frequencies of virulence factors on differentials “Fulhard” and “Early Premium” were high (>95%), whereas the virulence factor to differential “Triticum spelta var. Album” (Yr5) was not detected, while virulence to other differentials showed variable frequency within different counties. The predominant races in winter wheat in the same season were also detected from spring wheat cultivars, indicating Pst spreading from winter wheat to spring wheat crops. Deploying resistance genes in spring and winter wheat cultivars is critical for control stripe rust

Dietary Corn Bran Altered the Diversity of Microbial Communities and Cytokine Production in Weaned Pigs

Corn bran (CB) has been used as an ingredient for pigs, but the underlying mechanisms that improve gut health is less clear. This study was conducted to investigate effects of dietary CB on growth performance, nutrient digestibility, plasma indices related to gut hormones and immunity, gut microbiota composition, and fermentation products in weaned pigs. A total of 60 weaned pigs were allocated to two dietary treatments, and piglets in each group received control (CON) diet or 5% CB diet for 28 days. Growth performance, nutrient digestibility, indices of gut hormones and immunity in plasma were evaluated. Microbiota composition in feces was determined using 16S rRNA amplicon sequencing, and fermentation products were measured by high-performance ion chromatography. The results showed that dietary CB did not affect growth performance, nutrient digestibility, gut hormones, or fermentation products in the trial (P > 0.05). There was an increased response to CB inclusion on interleukin-10 production (P < 0.05). On day 28, piglets fed dietary CB had a higher shannon index (P < 0.05). The population of the Firmicutes in CB treatment were decreased (P < 0.05), while the percentage of the Bacteroidetes were increased (P < 0.05). In particular, the populations of Eubacterium corprostanoligenes, Pevotella, and Fibrobacter related to polysaccharide fermentation of cereal bran were increased (P < 0.05). In conclusion, a post-weaning diet containing 5% CB increased intestinal microbial diversity, especially higher richness of fibrolytic bacteria, and promoted anti-inflammatory response to some extent in piglets, these changes should facilitate the adaptation of the digestive system of piglets in the subsequent growing phases

Combination of Clostridium butyricum and Corn Bran Optimized Intestinal Microbial Fermentation Using a Weaned Pig Model

Experimental manipulation of the intestinal microbiota influences health of the host and is a common application for synbiotics. Here Clostridium butyricum (C. butyricum, C.B) combined with corn bran (C.B + Bran) was taken as the synbiotics application in a waned pig model to investigate its regulation of intestinal health over 28 days postweaning. Growth performance, fecal short chain fatty acids (SCFAs) and bacterial community were evaluated at day 14 and day 28 of the trial. Although the C.B + Bran treatment has no significant effects on growth performance (P > 0.05), it optimized the composition of intestinal bacteria, mainly represented by increased acetate-producing bacteria and decreased pathogens. Microbial fermentation in the intestine showed a shift from low acetate and isovalerate production on day 14 to enhanced acetate production on day 28 in the C.B + Bran treatment. Thus, C.B and corn bran promoted intestinal microbial fermentation and optimized the microbial community for pigs at an early age. These findings provide perspectives on the advantages of synbiotics as a new approach for effective utilization of corn barn

Sodium Decanoate Improves Intestinal Epithelial Barrier and Antioxidation via Activating G Protein-Coupled Receptor-43

The study was conducted to explore actions of decanoic acid on regulating intestinal barrier and antioxidant functions in intestinal epithelium cells isolated from porcine jejunum (IPEC-J2) and C57/BL6 mice models. In vitro and vivo assays, mice and IPEC-J2 cells treated by H2O2 were disposed of sodium decanoate and sodium butyrate to determine intestinal barrier and antioxidant functions of the host. Results showed that sodium decanoate upregulated expression of tight junction proteins and improved antioxidant capacity in both IPEC-J2 cells treated by H2O2 and mice models (p < 0.05). Sodium decanoate increased weight gain and ileal villus height of mice compared with control and sodium butyrate treatments (p < 0.05). Sodium decanoate increased α-diversity of ileal microbiota, volatile fatty acids concentration, and G protein-coupled receptor-43 (GPR-43) expression in the ileum and colon of mice (p < 0.05). In conclusion, sodium decanoate improved antioxidant capacity, intestinal morphology, and gut physical barrier of intestinal epithelial cells, resulting in an increase growth performance of mice, which is mediated through activating GPR-43 signaling

Study on Impermeability of Foamed Concrete Containing Municipal Solid Waste Incineration Powder

In this paper, the effects of dry density, w/c ratio, and municipal solid waste incineration (MSWI) powder on the multi-scale properties and internal pore structure of foamed concrete were studied by using a single-factor controlled experiment. It was found that an increase in the dry density of foamed concrete could effectively reduce the porosity, leading to the improvement of compressive strength and impermeability and to the reduction of water absorption. The compressive strength, water absorption, and impermeability were mainly affected by the porosity when the w/c ratio changed. With the increase in porosity, the water absorption rate increased, and the compressive strength and impermeability decreased. The addition of MSWI powder caused no obvious change in the overall pore size distribution of the foamed concrete, and there was no significant change in the water absorption and impermeability of the structure. However, because the hydration activity of MSWI powder was lower than that of ordinary Portland cement, the compressive strength of foamed concrete decreased with the increase in MSWI powder

Optimizing and accelerating history matching progress of numerical reservoir simulation by using material balance analysis

In view of the problem of huge computations and multiple solutions, a method for optimizing and accelerating the progress of history matching by using material balance analysis was established. Based on simple measuring data, such as average pressure, daily production rate and PVT test, a material balance model can be constructed for a three phase system of hydrocarbon reservoir. According to the material balance calculation, original oil in place and aquifer parameters can be obtained as optimized parameters for numerical simulation, which contributes to solve the multi-solutions problem of history matching. Besides, by conducting uncertainty analysis using Monte-Carlo simulation method, one can determine the adjustment range of input parameters, which helps the engineer definite a clear direction, reduce the number of computations and consequently accelerate the progress of history matching. The reliability of the proposed method was verified according to two examples