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Background Polysaccharides and ethanol extract from Polygonatum sibiricum rhizome were reported to improve high-fat diet (HFD)-fed mouse obesity. However, the effect and potential mechanism of Polygonatum sibiricum rhizome water extract (PSRwe) on HFD-induced obesity mice remains unclear. The present study was sought to comprehensively elucidate that. An obese mouse model was established by feeding HFD and PSRwe were intragastrically administered once a day for 40 days. Changes in body weight, gut microbiota and their metabolites, plasma and liver metabolomics, colonic and liver transcriptomics were explored. The compounds in PSRwe were also examined.Results Body weight was significantly reduced after two weeks of PSRwe administration. Meanwhile, PSRwe treatment has significantly recovered the richness and diversity of gut microbiota in HFD-caused obesity mice. Specifically, beneficial species including Akkermansia muciniphila and functional pathways including fatty acids biosythesis and elongation, pentose phosphate pathway, glycolysis and reductive TCA cycle were significantly enriched in PSRwe group compared with oebsity. RNA-seq revealed that the function of the up-regulated DEGs in liver of PSRwe mice were mainly concentrated on lipid and fatty acid oxidation and metabolism, while the down-regulated DEGs were mainly focused on sterols and sterol biosynthesis and metabolism. In colon, however, the function of up-regulated DEGs were primarily JAK-STAT/PI3K-Akt signaling pathway, regulation of GTPase activity, and response to cation while the down-regulated DEGs were centered on glycolysis, fructose/mannose/pyruvate metabolism, fat digestion and absorption, and PPAR signaling pathway. Metabolomics analysis indicated that betaine, an effective component from PSR water extracts, has showed higher levels in both liver and plasma of PSRwe-treated mice, indicating that it was significantly associated with obesity. In addition, correlation analysis showed that the significantly different species enriched in PSRwe group were negatively correlated with colonic DEGs related on PPAR signaling pathway, glycolysis etc. but positively correlated with JAK-STAT signaling pathway etc. Intriguingly, common metabolites in plasma and liver were negatively correlated with liver DEGs related on steroids and sterols biosynthesis and metabolism but positively correlated with fatty acid metabolism.Conclusions Collectively, our study demonstrated that PSRwe could significantly alleviate HFD-induced mouse obesity via either directly affect lipid metabolism through effective betaine or by changing gut microbiota and their metabolites to alter gene expression associated with fatty acid metabolism in liver and colon, suggesting PSRwe might be a promising therapeutic candidate for obesity in clinical.

Planarians are widely used as water quality indicator species to provide early warning of harmful pollution in aquatic ecosystems. However, the impact of microplastics on freshwater planarians remains poorly investigated. Here we simulated waterborne microplastic exposure in the natural environments to examine the effect on the antioxidant defense system and microbiota in Dugesia japonica. The results showed that exposure to microplastics significantly changed the levels of antioxidant enzymes, including superoxide dismutase, catalase, and glutathione S-transferase, indicating that microplastic exposure induces oxidative stress in planarians. High-throughput 16S rRNA gene sequencing results revealed that exposure to microplastics altered the diversity, abundance, and composition of planarian microbiota community. At phylum level, the relative abundance of the dominant phyla Proteobacteria and Bacteroidetes changed significantly after microplastic exposure. At genus level, the abundance of dominant genera also changed significantly, including Curvibacter and unclassified Chitinophagales. Predictive functional analysis showed that the microbiota of microplastic-exposed planarians exhibited an enrichment in genes related to fatty acid metabolism. Overall, these results showed that microplastics can cause oxidative stress and microbiota dysbiosis in planarians, indicating that planarians can serve as an indicator species for microplastic pollution in freshwater systems.

Train-track-bridge dynamic tests were conducted on the Shanghai Lingang Medium and Low Speed Maglev Test Line. A newly developed levitation bogie with mid-set air spring was used on the test train....

Based on the one-dimensional field theory for linear induction motor (LIM), the analytical model of two adjacent series motors was built, then the relationships between spacing and traction, curren...

Soybean, a typical short-day crop, is sensitive to photoperiod, which is a major limiting factor defining its north-to-south cultivation range. The long-juvenile (LJ) trait is controlled primarily by the J locus which has been used for decades by soybean breeders to delay flowering and improve grain yield in tropical regions. The J gene encodes an ortholog of the Arabidopsis Evening Complex (EC) component EARLY FLOWERING 3 (ELF3). To identify modifiers of J, we conducted a forward genetic screen and isolated a mutant (eoj57) that in combination with j has longer flowering delay compared with j single mutant plants. Map-based cloning and genome re-sequencing identified eoj57 (designated as GmLUX2) as an ortholog of the Arabidopsis EC component LUX ARRHYTHMO (LUX). To validate that GmLUX2 is a modifier of J, we used trans-complementation and identified a natural variant allele with a similar phenotype. We also show that GmLUX2 physically interacts with GmELF3a/b and binds DNA, whereas the mutant and natural variant are attenuated in both activities. Transcriptome analysis shows that the GmLUX2-GmELF3a complex co-regulates the expression of several circadian clock-associated genes and directly represses E1 expression. These results provide mechanistic insight into how GmLUX2-GmELF3 controls flowering time via synergistic regulation of gene expression. These novel insights expand our understanding of the regulation of the EC complex, and facilitate the development of soybean varieties adapted for growth at lower latitudes.

Meiotic recombination contributes to the maintenance of the association between homologous chromosomes (homologs) and ensures the accurate segregation of homologs during anaphase I, thus facilitating the redistribution of alleles among progeny. Meiotic recombination is initiated by the programmed formation of DNA double strand breaks, the repair of which requires DNA synthesis, but the role of DNA synthesis proteins during meiosis is largely unknown. Here, we hypothesized that the lagging strand-specific DNA Polymerase δ (POL δ) might be required for meiotic recombination, based on a previous analysis of DNA Replication Factor1 that suggested a role for lagging strand synthesis in meiotic recombination. In Arabidopsis (Arabidopsis thaliana), complete mutation of the catalytic subunit of POL δ, encoded by AtPOLD1, leads to embryo lethality. Therefore, we used a meiocyte-specific knockdown strategy to test this hypothesis. Reduced expression of AtPOLD1 in meiocytes caused decreased fertility and meiotic defects, including incomplete synapsis, the formation of multivalents, chromosome fragmentation, and improper segregation. Analysis of meiotic crossover (CO) frequencies showed that AtPOLD1(RNAi) plants had significantly fewer interference-sensitive COs than the wild type, indicating that AtPOL δ participates in type I CO formation. AtPOLD1(RNAi) atpol2a double mutant meiocytes displayed more severe meiotic phenotypes than those of either single mutant, suggesting that the function of AtPOLD1 and AtPOL2A is not identical in meiotic recombination. Given that POL δ is highly conserved among eukaryotes, we hypothesize that the described role of POL δ here in meiotic recombination likely exists widely in eukaryotes.

Rheumatoid arthritis (RA) is a systemic, chronic autoimmune disease involving synovial inflammation and joint destruction. Lack of knowledge on RA pathogenesis hinders development of effective treatments. The aim of this study was to examine whether circular RNAs (circRNAs), which are involved in the development of other diseases, may also play a role in RA. Expression profiles of circRNAs were compared between peripheral blood lymphocytes from RA patients and healthy controls. Candidate RA-associated circRNAs were validated using RT-PCR, and interactions with target microRNAs were predicted. Analysis of circRNA microarrays identified 689 circRNAs expressed at significantly different levels between RA patients and controls (p < 0.05), of which 95 were up-regulated and 594 down-regulated in RA. Microarray analysis was corroborated by RT-PCR for hsa_circRNAs 103571, 101319, 102034, 103503 and 100257. Potential target miRNAs for hsa_circRNAs were predicted. Several circRNAs in peripheral blood lymphocytes may be differentially expressed in RA (hsa_circRNAs 103571, 101319, 102034, 103503 and 100257). These circRNAs may serve as potential targets for RA diagnosis and treatment. Key words: Circular RNA, microarray, rheumatoid arthritis, microRNA.

Molybdenum naphthenate was used as a catalyst to study the effects of the catalyst dosage on the product distribution, and the properties of suspended coke (Cokesus) and depositional coke (Cokedep) during slurry-bed hydrocracking of an atmospheric residue from Merey. The colloidal stability of product system, microscopic appearance of catalysts in coke, and the types and relative contents of Mo on coke surface were also investigated to elucidate the reason for those effects. The results showed that adding the Mo catalyst restrained the coke formation effectively, particularly the Cokedep. With the increase in catalyst dosage, the H2 consumption, gas, light oil, Cokesus, and Cokedep yields all initially decreased and then increased, while the conversion rate of raw materials initially increased and then decreased. In all cases, the highest yields were obtained at the same catalyst dosage. This indicated that increasing the catalyst dosage did not always improve the catalytic effect. The change trends of the colloidal stability of product system and the relative Mo4+ content on coke surface were consistent with the change trend of hydrogenation effects as the catalyst dosage increased. Increasing the catalyst dosage could result in the formation of more Mo4+ species with higher hydrogenation activity than other Mo valence states, which improved the system colloidal stability. However, when catalyst dosage exceeded a certain threshold, further increase decreased the relative Mo4+ content and reduced the system colloidal stability. This accounts for the influence of the catalyst dosage on the catalytic effects toward the heavy oil slurry-bed hydrocracking reaction.

Roots of leguminous plants perceive Nod factor signals, and then root hair deformation responses such as swelling and curling are activated. However, very little is known about the molecular mechanisms of such root hair deformation. We have previously shown that LjROP6, a member of the Rho family of small GTPases, was identified as an NFR5 (Nod Factor Receptor 5)-interacting protein and participated in symbiotic nodulation in Lotus japonicus. In this study, we identified ten LjROP GTPases including LjROP6, and they were distributed into groups II, III, IV but not group I by phylogenetic analysis. The expression profiles of ten LjROP genes during nodulation were examined. LjROP6 belonged to group IV and interacted with NFR5 in a GTP-dependent manner. Overexpression of either wild-type ROP6 or a constitutively active mutant (ROP6-CA) generated root hair tip growth depolarization, while overexpression of a dominant negative mutant (ROP6-DN) exhibited normal root hair growth. After inoculating with Mesorhizobium loti or adding Nod factors to hairy roots, overexpression of ROP6 and ROP6-CA exhibited extensive root hair deformation, while overexpression of ROP6-DN inhibited root hair deformation. The infection event and nodule number were increased in ROP6 and ROP6-CA overexpressing transgenic plants; but decreased in ROP6-DN overexpressing transgenic plants. These studies provide strong evidence that ROP6 GTPase, which binds NFR5 in a GTP-dependent manner, is involved in root hair development as well as root hair deformation responses induced by NFs in the early stage of symbiotic interaction in L. japonicus.

Amino acid transporters (AATs) play important roles in transporting amino acid across cellular membranes and are essential for plant growth and development. To date, the AAT gene family in soybean (Glycine max L.) has not been characterized. In this study, we identified 189 AAT genes from the entire soybean genomic sequence, and classified them into 12 distinct subfamilies based upon their sequence composition and phylogenetic positions. To further investigate the functions of these genes, we analyzed the chromosome distributions, gene structures, duplication patterns, phylogenetic tree, tissue expression patterns of the 189 AAT genes in soybean. We found that a large number of AAT genes in soybean were expanded via gene duplication, 46 and 36 GmAAT genes were WGD/segmental and tandemly duplicated, respectively. Further comprehensive analyses of the expression profiles of GmAAT genes in various stages of vegetative and reproductive development showed that soybean AAT genes exhibited preferential or distinct expression patterns among different tissues. Overall, our study provides a framework for further analysis of the biological functions of AAT genes in either soybean or other crops.