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Skeletal muscle is not only the largest organ in the body that is responsible for locomotion and exercise but also crucial for maintaining the body’s energy metabolism and endocrine secretion. The trimethylation of histone H3 lysine 27 (H3K27me3) is one of the most important histone modifications that participates in muscle development regulation by repressing the transcription of genes. Previous studies indicate that the RASGRP1 gene is regulated by H3K27me3 in embryonic muscle development in pigs, but its function and regulatory role in myogenesis are still unclear. In this study, we verify the crucial role of H3K27me3 in RASGRP1 regulation. The gain/loss function of RASGRP1 in myogenesis regulation is performed using mouse myoblast C2C12 cells and primarily isolated porcine skeletal muscle satellite cells (PSCs). The results of qPCR, western blot analysis, EdU staining, CCK-8 assay and immunofluorescence staining show that overexpression of RASGRP1 promotes cell proliferation and differentiation in both skeletal muscle cell models, while knockdown of RASGRP1 leads to the opposite results. These findings indicate that RASGRP1 plays an important regulatory role in myogenesis in both mice and pigs.

Birth weight is a complex multifactorial trait relevant to health states and disease risks in later life. The placenta is essential for proper fetal growth and facilitates gas, nutrient, and waste exchange between the mother and developing fetus. How changes in placental DNA methylation affect fetal birth weight remains to be fully elucidated. In this study, we used whole-genome bisulfite sequencing and RNA sequencing to reveal a global map of DNA methylation and gene expression changes between the placentas of highest birth weight and lowest birth weight piglets in the same litters. The transcriptome analysis identified 1682 differential expressed genes and revealed key transcriptional properties in distinct placentas. We also identified key transcription factors that may drive the differences in DNA methylome patterns between placentas. The decrease in DNA methylation level in the promoter was associated with the transcriptional activation of genes associated with angiogenesis, extracellular matrix remodeling, and transmembrane transport. Our results revealed the regulatory role of DNA methylation in gene transcription activity leading to the differences in placental morphological structures and birth weights of piglets. These results could provide novel clues to clarify the underlying regulatory mechanisms of placental development and fetal growth. [ABSTRACT FROM AUTHOR]

Recently, the piezoelectric effect has been widely used in photoelectrochemical (PEC) water splitting, and the morphology of the piezoelectric material is a critical factor affecting the piezo-photoelectrochemical water splitting performance. Herein, we explored the mechanism of the piezo-photoelectrochemical performance of zinc oxide (ZnO) that is affected by the morphology. Firstly, three different ZnO nanostructures (nanosheets, nanorods, and nanospheres) were synthesized by the electrodeposition, hydrothermal, and sol-gel methods, respectively. Then, the measurements of PEC water splitting performance under the piezoelectric effect revealed a 3-fold increase for the ZnO nanosheets, a 1.4-fold increase for the nanorods, and a 1.2-fold increase for the nanospheres compared to no piezoelectric effect. Finally, finite element simulation showed that nanosheets generated the highest piezoelectric potential (0.6 V), followed by nanorods (0.2 V), and nanospheres the lowest (0.04 V). Thus, among the three morphologies, the ZnO nanosheets exhibited a great improvement in PEC performance under the piezoelectric effect. The great improvement is due to the non-axial vertical homogeneous growth of the ZnO nanosheets, subjecting them to the highest effective deformation stress, which enables the ZnO nanosheets to produce the highest piezoelectric potential to accelerate the carrier separation and limit the recombination of photoelectrons and holes. This work serves as a guide for developing various photoelectrodes that are used in piezo-photoelectrochemical water splitting. [ABSTRACT FROM AUTHOR]

Summary: In this work, we reported a reasonable, simple, and low cost strategy that Cu2O is decorated with Cu layer and Al layer to realize the improvement of photoelectrochemical (PEC) performance. The results indicate that the Cu/Al layer that has surface plasmon resonance (SPR) effect inherits both properties of which Cu has high conductivity and Al could form thin Al2O3 layer to hinder Fermi‐level pinning to accelerate the transfer of photoinduced electron‐hole pairs. With the synergistic effect of Cu and Al, Cu/Al/Cu2O photocathode displays a higher photocurrent density (−2.16 mA/cm2 at 0 V vs RHE), which is 3.7 times as high as the pure Cu2O. Thus, loading bimetallic is believed to be an effective strategy and could inspire interest in continuing to explore novel and effective bimetallic catalysts for PEC water splitting. [ABSTRACT FROM AUTHOR]

When the automobile exhaust thermoelectric generator system was connected to the ex-haust pipe of the engine, the airflow would be changed. In order to minimize the impacts on the original performance of the engines and improve the electrical power generation performance of the automobile exhaust thermoelectric generator systems, a hexagonal heat exchanger used for an automobile exhaust thermoelectric generator system was optimized for the on-board compatibility with the goal of the highest average surface temperature and the smallest pressure loss. A finite element simulation model of the heat exchanger was bit based on CFD software to study the influences of the inlet gas speed of the heat exchanger on the surface temperature and pressure loss, as well as the influences of the inlet gas temperature on the surface temperature. The tins length, tins angle, tins width and tins spacing were taken as the design variables. The Gaussian process regression proxy model was established based on the test data, and the grey wolf algorithm was used to obtain the optimal solution in the multi-objective optimization function space. The results show that compared with the classical NSGA-algorithm, the Pareto solution set obtained by multi-objective grey wolf algorithm is more concentrated and the evaluation index is higher. The optimized heat exchanger with multi-objective grey wolf algorithm has a lower surface average temperature than that of several structures before optimization, but the pressure loss is significantly reduced. Compared with the cavity structure heat exchanger, the surface average temperature and pressure loss of optimized heat exchanger increase, and the pressure loss increasing amplitudes are within the acceptable ranges. The optimized heat exchanger may effectively take into account the power generation of the automobile exhaust thermoelectric generator systems and the on-board compatibility. [ABSTRACT FROM AUTHOR]

N6-methyladenosine (m6A) is the most common modification in eukaryotic RNAs. Accumulating evidence shows m6A methylation plays vital roles in various biological processes, including muscle and fat differentiation. However, there is a lack of research on lncRNAs' m6A modification in regulating pig muscle-fiber-type conversion. In this study, we identified novel and differentially expressed lncRNAs in oxidative and glycolytic skeletal muscles through RNA-seq, and further reported the m6A-methylation patterns of lncRNAs via MeRIP-seq. We found that most lncRNAs have one m6A peak, and the m6A peaks were preferentially enriched in the last exon of the lncRNAs. Interestingly, we found that lncRNAs' m6A levels were positively correlated with their expression homeostasis and levels. Furthermore, we performed conjoint analysis of MeRIP-seq and RNA-seq data and obtained 305 differentially expressed and differentially m6A-modified lncRNAs (dme-lncRNAs). Through QTL enrichment analysis of dme-lncRNAs and PPI analysis for their cis-genes, we finally identified seven key m6A-modified lncRNAs that may play a potential role in muscle-fiber-type conversion. Notably, inhibition of one of the key lncRNAs, MSTRG.14200.1, delayed satellite cell differentiation and stimulated fast-to-slow muscle-fiber conversion. Our study comprehensively analyzed m6A modifications on lncRNAs in oxidative and glycolytic skeletal muscles and provided new targets for the study of pig muscle-fiber-type conversion. [ABSTRACT FROM AUTHOR]