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Ovule initiation is a key step that strongly influences ovule number and seed yield. Notably, mutants with enhanced brassinosteroid (BR) and cytokinin (CK) signaling produce more ovules and have a higher seed number per silique (SNS) than wild-type plants. Here, we crossed BR- and CK-related mutants to test whether these phytohormones function together in ovule initiation. We determined that simultaneously enhancing BR and CK contents led to higher ovule and seed numbers than enhancing BR or CK separately, and BR and CK enhanced each other. Further, the BR-response transcription factor BZR1 directly interacted with the CK-response transcription factor ARABIDOPSIS RESPONSE REGULATOR1 (ARR1). Treatments with BR or BR plus CK strengthened this interaction and subsequent ARR1 targeting and induction of downstream genes to promote ovule initiation. Enhanced CK signaling partially rescued the reduced SNS phenotype of BR-deficient/insensitive mutants whereas enhanced BR signaling failed to rescue the low SNS of CK-deficient mutants, suggesting that BR regulates ovule initiation and SNS through CK-mediated and CK-independent pathways. Our study thus reveals that interaction between BR and CK promotes ovule initiation and increases seed number, providing important clues for increasing the seed yield of dicot crops. This article is protected by copyright. All rights reserved.

Background Interferon regulatory factor 2 (IRF-2) acts as an anti-oncogene in gastric cancer (GC); however, the underlying mechanism remains unknown. Methods This study determined the expression of IRF-2 in GC tissues and adjacent non-tumor tissues using immunohistochemistry (IHC) and explored the predictive value of IRF-2 for the prognoses of GC patients. Cell function and xenograft tumor growth experiments in nude mice were performed to test tumor proliferation ability, both in vitro and in vivo. Chromatin immunoprecipitation sequencing (ChIP-Seq) assay was used to verify the direct target of IRF-2. Results We found that IRF-2 expression was downregulated in GC tissues and was negatively correlated with the prognoses of GC patients. IRF-2 negatively affected GC cell proliferation both in vitro and in vivo. ChIP-Seq assay showed that IRF-2 could directly activate AMER-1 transcription and regulate the Wnt/β-catenin signaling pathway, which was validated using IHC, in both tissue microarray and xenografted tumor tissues, western blot analysis, and cell function experiments. Conclusions Increased expression of IRF-2 can inhibit tumor growth and affect the prognoses of patients by directly regulating AMER-1 transcription in GC and inhibiting the Wnt/β-catenin signaling pathway.

Background:. Investigations of the pathogenic mechanisms in motor neurons (MNs) derived from amyotrophic lateral sclerosis (ALS) disease-specific induced pluripotent stem (iPS) cell lines could improve understanding of the issues affecting MNs. Therefore, in this study we explored mutant superoxide dismutase 1 (SOD1) protein expression in MNs derived from the iPS cell lines of ALS patients carrying different SOD1 mutations. Methods:. We generated induced pluripotent stem cell (iPSC) lines from two familial ALS (FALS) patients with SOD1-V14M and SOD1-C111Y mutations, and then differentiated them into MNs. We investigated levels of the SOD1 protein in iPSCs and MNs, the intracellular Ca2+ levels in MNs, and the lactate dehydrogenase (LDH) activity in the process of differentiation into the MNs derived from the controls and ALS patients’ iPSCs. Results:. The iPSCs from the two FALS patients were capable of differentiation into MNs carrying different SOD1 mutations and differentially expressed MN markers. We detected high SOD1 protein expression and high intracellular calcium levels in both the MN and iPSCs that were derived from the two SOD1 mutant patients. However, at no time did we observe stronger LDH activity in the patient lines compared with the control lines. Conclusions:. MNs derived from patient-specific iPSC lines can recapitulate key aspects of ALS pathogenesis, providing a cell-based disease model to further elucidate disease pathogenesis and explore gene repair coupled with cell-replacement therapy. Incremental mutant expressions of SOD1 in MNs may have disrupted MN function, either causing or contributing to the intracellular calcium disturbances, which could lead to the occurrence and development of the disease.

Background:. Ubiquitin-conjugating enzyme E2C (UBE2C) has been shown to be associated with the occurrence of various cancers and involved in many tumorigenic processes. This study aimed to investigate the specific molecular mechanism through which UBE2C affects breast cancer (BC) proliferation. Methods:. BC-related datasets were screened according to filter criteria in the Gene Expression Omnibus (GEO) database and The Cancer Genome Atlas (TCGA) database. Then differentially expressed genes (DEGs) were identified using Venn diagram analysis. By using DEGs, we conducted the following analyses including Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), protein–protein interaction (PPI), and survival analysis, and then validated the function of the hub gene UBE2C using quantitative reverse transcription-polymerase chain reaction (RT-qPCR), cell counting kit-8 (CCK-8) assay, transwell assay, and Western blot assay. Results:. In total, 151 DEGs were identified from the GEO and TCGA databases. The results of GO analysis demonstrated that the DEGs were significantly enriched with mitotic nuclear division, lipid droplet, and organic acid-binding. KEGG analysis showed that the peroxisome proliferators-activated receptor (PPAR) signaling pathway, regulation of lipolysis in adipocytes, and proximal tubule bicarbonate reclamation were significantly enriched in the signal transduction pathway category. The top three hub genes that resulted from the PPI network were FOXM1, UBE2C, and CDKN3. The results of survival analysis showed a close relationship between UBE2C and BC. The results of CCK-8 and transwell assays suggested that the proliferation and invasion of UBE2C knockdown cells were significantly inhibited (P

Bitter melon (Momordica charantia) has traditionally been used in the management of diabetes in many countries and territories. However, standardized information on the use of this vegetable as an ...

Background:. Age-related macular degeneration (AMD) is the leading cause of vision loss worldwide. However, the mechanisms involved in the development and progression of AMD are poorly delineated. We aimed to explore the critical genes involved in the progression of AMD. Methods:. The differentially expressed genes (DEGs) in AMD retinal pigment epithelial (RPE)/choroid tissues were identified using the microarray datasets GSE99248 and GSE125564, which were downloaded from the gene expression omnibus database. The overlapping DEGs from the two datasets were screened to identify DEG-related biological pathways using gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses. The hub genes were identified from these DEGs through protein-protein interaction network analyses. The expression levels of hub genes were evaluated by quantitative real-time polymerase chain reaction following the induction of senescence in ARPE-19 with FK866. Following the identification of AMD-related key genes, the potential small molecule compounds targeting the key genes were predicted by PharmacoDB. Finally, a microRNA-gene interaction network was constructed. Results:. Microarray analyses identified 174 DEGs in the AMD RPE compared to the healthy RPE samples. These DEGs were primarily enriched in the pathways involved in the regulation of DNA replication, cell cycle, and proteasome-mediated protein polyubiquitination. Among the top ten hub genes, HSP90AA1, CHEK1, PSMA4, PSMD4, and PSMD8 were upregulated in the senescent ARPE-19 cells. Additionally, the drugs targeting HSP90AA1, CHEK1, and PSMA4 were identified. We hypothesize that Hsa-miR-16-5p might target four out of the five key DEGs in the AMD RPE. Conclusions:. Based on our findings, HSP90AA1 is likely to be a central gene controlling the DNA replication and proteasome-mediated polyubiquitination during the RPE senescence observed in the progression of AMD. Targeting HSP90AA1, CHEK1, PSMA4, PSMD4, and/or PSMD8 genes through specific miRNAs or small molecules might potentially alleviate the progression of AMD through attenuating RPE senescence.

Background:. Deep brain stimulation (DBS) has seizure-suppressing effects but the molecular mechanisms underlying its therapeutic action remain unclear. This study aimed to systematically elucidate the mechanisms underlying DBS-induced seizure suppression at a molecular level. Methods:. We established a macaque model of mesial temporal lobe epilepsy (mTLE), and continuous high-frequency hippocampus DBS (hip-DBS) was applied for 3 months. The effects of hip-DBS on hippocampus gene expression were examined using high-throughput microarray analysis followed by bioinformatics analysis. Moreover, the microarray results were validated using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analyses. Results:. The results showed that chronic hip-DBS modulated the hippocampal gene expression. We identified 4119 differentially expressed genes and assigned these genes to 16 model profiles. Series test of cluster analysis showed that profiles 5, 3, and 2 were the predominant expression profiles. Moreover, profile 5 was mainly involved in focal adhesion and extracellular matrix-receptor interaction pathway. Nine dysregulated genes (Arhgap5, Col1a2, Itgb1, Pik3r1, Lama4, Fn1, Col3a1, Itga9, and Shc4) and three genes (Col1a2, Itgb1, and Flna) in these two pathways were further validated by qRT-PCR and Western blot analyses, respectively, which showed a concordance. Conclusion:. Our findings suggest that hip-DBS could markedly reverse mTLE-induced abnormal gene expression. Findings from this study establish the basis for further investigation of the underlying regulatory mechanisms of DBS for mTLE.

The objective of this study is to investigate the effect of dietary glucose oxidase (GOx) supplementation on the reproductive performance, litter performance, total tract digestibility, and blood profile of lactating sows fed corn-wheat-based diet. A total of twenty multiparous sows (Landrace × Yorkshire) were allocated into one of four treatments with five replicates per treatment. The dietary treatments were as follows: CON (Basal diet), GO1 (basal diet + 200 U GOx/kg), GO2 (basal diet + 300 U GOx/kg), GO3 (basal diet + 400 U Gox/kg). Dietary GOx supplementation did not affect lactating sow’s reproduction performance as well as body weight, backfat thickness, and body condition score during pre and post farrowing, and at weaning (p > 0.05). However, after farrowing to weaning period lactating sow’s fed GOx supplement has linearly (p = 0.0196) decreased the bodyweight loss. While, there were no effects (p > 0.05) observed on sows backfat thickness loss, average daily feed intake, and estrus interval among treatment groups. Dietary supplementation of GOx has linearly improved the body weight gain (p = 0.049) and average daily gain (p = 0.040) of suckling piglets. The total tract digestibility of dry matter and nitrogen was linearly increased with the graded level of GOx supplement. Also, a linear effect was observed on the glucose and superoxide dismutase of blood profile with the dietary inclusion of GOx. In summary, our finding indicates that the dietary inclusion of GOx supplement with corn-wheat-based diet had a beneficial effect on the nutrient digestibility and blood profile of lactating sows and improved the growth performance of suckling piglets.

Recent studies have shown that global metabolic reprogramming is a common event in plant innate immunity; however, the relevant molecular mechanisms remain largely unknown. Here, we identified a pathogen-induced glycosyltransferase, UGT73C7, that plays a critical role in Arabidopsis disease resistance through mediating redirection of the phenylpropanoid pathway. Loss of UGT73C7 function resulted in significantly decreased resistance to Pseudomonas syringae pv. tomato DC3000, whereas constitutive overexpression of UGT73C7 led to an enhanced defense response. UGT73C7-activated immunity was demonstrated to be dependent on the upregulated expression of SNC1, a Toll/interleukin 1 receptor-type NLR gene. Furthermore, in vitro and in vivo assays indicated that UGT73C7 could glycosylate p-coumaric acid and ferulic acid, the upstream metabolites in the phenylpropanoid pathway. Mutations that lead to the loss of UGT73C7 enzyme activities resulted in the failure to induce SNC1 expression. Moreover, glycosylation activity of UGT73C7 resulted in the redirection of phenylpropanoid metabolic flux to biosynthesis of hydroxycinnamic acids and coumarins. The disruption of the phenylpropanoid pathway suppressed UGT73C7-promoted SNC1 expression and the immune response. This study not only identified UGT73C7 as an important regulator that adjusts phenylpropanoid metabolism upon pathogen challenge, but also provided a link between phenylpropanoid metabolism and an NLR gene.

Paeonia ludlowii, a plant of the Paeoniaceae family, has abundant genetic diversity in different populations, and the seed oil can be used in a diverse number of activities. However, its neuroprotective effect is not clear. We investigated the memory‐improving effects and associated mechanisms of Paeonia ludlowii seed oil (PLSO) on amyloid beta (Aβ)25–35‐induced Alzheimer's disease (AD) in rats. The Morris water maze test was undertaken, and subsequently, the content of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), and acetylcholinesterase (ACHE) in the hippocampus was detected by biochemical analyses. To further study PLSO, we examined the pathologic structure and apoptosis of hippocampal tissue by staining. Immunohistochemical analysis was used to detect expression of IBA‐1 and GFAP in the hippocampus. Detection of proinflammatory factors was achieved by reverse transcription–quantitative polymerase chain reaction and Western blotting. High‐dose PLSO inhibited expression of GFAP and IBA‐1. We demonstrated that high‐dose PLSO can regulate activation of glial cells and mediate apoptosis of hippocampal cells, and significantly improve learning and memory deficits in AD rats. PLSO could be developed as a nutritional supplement and sold as a drug for AD prevention and/or treatment.

Hypoxia induced by flooding or submergence is a serious abiotic stress affecting crop productivity worldwide. During evolution, plants have developed different metabolism mechanisms to cope with the energy crisis caused by hypoxia stress. Among those, the metabolism of γ-aminobutyric acid (GABA), a non-protein amino acid, is recognized as a crucial component for low-oxygen stress responses because of its link both in carbon and nitrogen metabolism. However, it is largely unknown how to control GABA homeostasis. In this study, we identified a novel glycosyltransferase encoding gene, UGT79B7, which was significantly downregulated by low-oxygen treatment in Arabidopsis. ugt79b7 knockout mutants showed increased resistance to hypoxia, while the overexpression lines showed increased sensitivity. We demonstrated that glycosyltransferase UGT79B7 could catalyze GABA to form GABA glucose conjugate (GABA-Glc) in vitro. The in vivo biochemical function of UGT79B7 in controlling GABA glycosylation was also verified. Moreover, we also demonstrated that UGT79B7 could negatively modulate the accumulation of GABA under hypoxia stress. Our data suggest that the glycosylation of GABA plays an important role in GABA homeostasis and reveal a new way for the regulation of plant hypoxia response through a dynamic balance of GABA and its glycosylation products, GABA-Glc.

The aim of this study was to identify members of potato GATA gene (StGATA) family and to provide information for further study on the regulatory role of StGATA transcription factors in potato growth and development and biotic and abiotic stresses. Based on the whole potato genome data, the members of potato GATA transcription factor family were identified and systematically analyzed by bioinformatics online analysis website and software. In total, forty-nine GATA proteins from Solanum tuberosum were identified. Phylogenetic analysis revealed that these GATA proteins could be divided into 5 subfamilies. The gene structure and conserved motif analysis revealed that many genes have more than one intron. Forty-nine StGATA genes were distributed on 12 chromosomes randomly. A cis-element analysis inferred that StGATAs contain abiotic stress-related elements. A heatmap showed that many StGATAs are generally expressed in tissues at different developmental stages. A representative member StGATA9 was selected for screening its expression characteristics to identify whether it was induced by Ralstonia solanacearum, abscisic acid (ABA) and methyl jasmonate (MJ) treatment. Quantitative real-time polymerase chain reaction (qRT-PCR) assays indicated that StGATA9 was induced by R. solanacearum. And StGATA9 was up-regulated by different concentrations of ABA and MJ. Tissue localization showed that StGATA9 was mainly expressed in phloem of leaf vascular bundles and stem vascular system. These results provide a theoretical basis for further experimental cloning and functional verification of the gene, while provides a theoretical basis for the study of molecular mechanism of resistance to bacterial wilt in potato.

Aphids are infected by a series of bacteria that can help them survive on specific host plants. However, the associations between aphids and these bacteria are not clear, and the bacterial communities in many aphid species are poorly characterized. Here, we investigated the bacterial communities of cotton aphids (Aphis gossypii) on 2 representative winter host plants and transferred to 3 summer host plants by 16S rDNA sequencing using the Illumina MiSeq platform. Our results revealed that the bacterial communities varied among cotton aphids on hibiscus, cotton aphids on pomegranate, cotton aphids on cotton transferred from hibiscus, cotton aphids on muskmelon transferred from hibiscus, cotton aphids on cucumber transferred from hibiscus,. The diversity and richness of the bacterial communities were significantly higher in aphids on muskmelon and aphids on cucumber than in the other treatments. There were two main factors influencing the distribution of internal bacterial OTUs revealed by principal component analysis, including the differences among Punicaceae, Malvaceae and Cucurbitaceae. There were 28 bacterial communities with significant differences between two arbitrary treatments, which could be grouped into 6 main clusters depending on relative abundance. Moreover, our results indicated that in addition to the obligate endosymbiont Buchnera, with a dominant position (> 52%), A. gossypii also harbored 3 facultative endosymbiotic bacteria (Serratia, Arsenophonus, and Wolbachia) and 3 possibly symbiotic bacteria (Acinetobacter, Pantoea, and Flavobacterium). There were several correspondences between the symbiotic bacteria in cotton aphids and the specific host plants of the aphids. This study provides a better understanding of the interactions among symbiotic bacteria, aphids and host plants, suggesting that the selection pressure on aphid bacterial communities is likely to be exerted by the species of host plants.

Aim: To investigate the expression profiles of circRNAs after intracerebral hemorrhage (ICH). Materials & methods: RNA sequencing and qRT-PCR were used to investigate and validate circRNA expression levels. Bioinformatics analysis was performed to explore potential functions of the circRNAs. Results: Expression levels of 15 circRNAs were consistently altered in patients with ICH compared with their expression levels in hypertension. Three circRNAs, hsa_circ_0001240, hsa_circ_0001947 and hsa_circ_0001386, individually or combined, were confirmed as promising biomarkers for predicting and diagnosing ICH. The circRNAs were involved mainly in lysine degradation and the immune system. Conclusion: This is the first study to report expression profiles of circRNAs after ICH and to propose that three circRNAs are potential biomarkers for ICH.

Background. Autophagy of alveolar macrophages is a crucial process in ischemia/reperfusion injury-induced acute lung injury (ALI). Bone marrow-derived mesenchymal stem cells (BM-MSCs) are multipotent cells with the potential for repairing injured sites and regulating autophagy. This study was to investigate the influence of BM-MSCs on autophagy of macrophages in the oxygen-glucose deprivation/restoration (OGD/R) microenvironment and to explore the potential mechanism. Methods. We established a co-culture system of macrophages (RAW264.7) with BM-MSCs under OGD/R conditions in vitro. RAW264.7 cells were transfected with recombinant adenovirus (Ad-mCherry-GFP-LC3B) and autophagic status of RAW264.7 cells was observed under a fluorescence microscope. Autophagy-related proteins light chain 3 (LC3)-I, LC3-II, and p62 in RAW264.7 cells were detected by Western blotting. We used microarray expression analysis to identify the differently expressed genes between OGD/R treated macrophages and macrophages co-culture with BM-MSCs. We investigated the gene heme oxygenase-1 (HO-1), which is downstream of the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signaling pathway. Results. The ratio of LC3-II/LC3-I of OGD/R treated RAW264.7 cells was increased (1.27 ± 0.20 vs. 0.44 ± 0.08, t = 6.67, P

The stemness of different side population (SP) cell subtypes in ovarian cancer cells was studied, and the heterogeneity of ovarian cancer stem cells was analyzed. The cisplatin-resistant human serous ovarian cancer cell line C13 was stained with the bisbenzimide Hoechst 33342. A flow cytometry-based fluorescence-activated sorting method was used to obtain lower-SP (LSP) cells, upper-SP (USP) cells, and non-SP cells (NSP) based on their sensitivity to the staining time and Hoechst dye concentration. The sphere-forming capability, expression levels of stem cell markers, resistance to high concentrations of cisplatin, and subcutaneous tumorigenicity in NOD/SCID mice of the different cell subtypes were evaluated. The C13 cells contained SP cells with stemness characteristics, and the LSP cell subtype expressed higher levels of stem cell markers, had higher in vitro sphere-forming capability, higher cisplatin resistance and higher in vivo subcutaneous tumorigenesis than USP cells (P

The yield and quality of the medicinal plant Achyranthes bidentata can be increased when it is replanted into a field cultivated previously with the same crop, however, fundamental aspects of its biology (so-called “replanting benefit”) still remain to be elucidated. miRNAs are sRNA molecules involved in the post-transcriptional regulation of gene expression in plant biological processes. Here, 267 conserved and 36 novel miRNAs were identified in A. bidentata roots. We compared the miRNA content of the roots (R1) from first-year planting with that of the roots (R2) of second-year replanting, and screened 21 differentially expressed (DE) miRNAs. Based on in silico functional analysis, integrated miRNA-mRNA datasets allowed the identification of 10 miRNA-target family modules, which might participate in the benefit. The expression profiles of the miRNA-target modules were potentially correlated with the presence of the replanting benefit. The indication was that the miRNA-responsive continuous monoculture could reprogram miRNA-mRNA expression patterns, which possibly promote the root growth and development, enhance its transport activity and strengthen its tolerance to various stresses, thereby improving A. bidentata productivity as observed in the replanting benefit. Our study provides basic data for further research on the molecular mechanisms of the benefit in A. bidentata.

To evaluate whether the efficacy of Getong Tongluo Capsule (葛酮通络胶囊, GTC, consisted of total flavone of Radix Puerariae) on improving patients’ quality of life and lowering blood pressure are superior to the extract of Ginkgo biloba (EGB) for patients with convalescent-phase ischemic stroke and primary hypertension. This randomized, positive-drug- and placebo-controlled, double-blind trial was conducted from September 2015 to October 2017. Totally 477 eligible patients from 18 hospitals in China were randomly assigned in a 2:1:1 ratio to the following interventions, twice a day for 12 weeks: (1) GTC 250 mg plus EGB-matching placebo 40 mg (237 cases, GTC group), (2) EGB 40 mg plus GTC-matching placebo 250 mg (120 cases, EGB group) or (3) GTC-matching placebo 250 mg plus EGB-matching placebo 40 mg (120 cases, placebo group). Moreover, all patients were orally administered aspirin enteric-coated tablets 100 mg, once a day for 12 weeks. The primary outcome was the Barthel Index (BI). The secondary outcomes included the control rate of blood pressure and National Institutes of Health Stroke Scale (NIHSS) scores. The incidence and severity of adverse events (AEs) were calculated and assessed. The BI relative independence rates, the clinical recovery rates of NIHSS, and the total effective rates of NIHSS in the GTC and EGB groups were significantly higher than the placebo group at 12 weeks after treatment (P 0.05). The control rate of blood pressure in the GTC group was significantly higher than the EGB and placebo groups at 12, 18 and 24 weeks after treatment (P 0.05). GTC exhibited significant efficacy in improving patients’ quality of life as well as neurological function and controlling hypertension. (Registration No. ChiCTR1800016667)

Background:. Epithelial to mesenchymal transition (EMT) is strongly linked with tumor invasion and metastasis, which performs a vital role in carcinogenesis and cancer progression. Emerging evidence suggests that microRNAs (miRNAs) expression are closely associated to EMT by regulating targeted genes. MiR542 has been found to be involved in the EMT program and bound up with various cancers. However, the functions of miR542 and its underlying mechanism in glioblastoma multiforme (GBM) remain largely unknown. In the current study, we investigated the effect of astrocyte elevated gene-1 (AEG-1) on U251 cells aggressiveness, proliferation, apoptosis, and cell cycle. Methods:. The screening of targeted miRNAs was performed, as well as the functional roles and mechanisms of miR542 were explored. Results:. MiR542 was selected as the target because of the most significantly differential expression and this high level of expression negatively correlated with cell migration and proliferation, which suggested that miR542 could be a novel tumor suppressor. Moreover, we confirmed that AEG-1 was a direct targeted gene of miR542 by luciferase activity assay, reverse transcription-polymerase chain reaction, and immunoblotting analysis. Furthermore, miR542 suppressed the expression of AEG-1, which upgraded the level of E-cadherin and degraded Vimentin expression contributing to retraining EMT. Conclusion:. The in vitro findings demonstrated that miR542 inhibited the migration and proliferation of U251 cells and suppressed EMT through targeting AEG-1, indicating that miR542 may be a potential anti-cancer target for GBM.

Hypoxia causes a series of responses supporting cells to survive in harsh environments. Substantial post-transcriptional and translational regulation during hypoxia has been observed. However, detailed regulatory mechanism in response to hypoxia is still far from complete. RNA m6A modification has been proven to govern the life cycle of RNAs. Here, we reported that total m6A level of mRNAs was decreased during hypoxia, which might be mediated by the induction of m6A eraser, ALKBH5. Meanwhile, expression levels of most YTH family members of m6A readers were systematically down-regulated. Transcriptome-wide analysis of m6A revealed a drastic reprogramming of m6A epitranscriptome during cellular hypoxia. Integration of m6A epitranscriptome with either RNA-seq based transcriptome analysis or mass spectrometry (LC-MS/MS) based proteome analysis of cells upon hypoxic stress revealed that reprogramming of m6A epitranscriptome reshaped the transcriptome and proteome, thereby supporting efficient generation of energy for adaption to hypoxia. Moreover, ATP production was blocked when silencing an m6A eraser, ALKBH5, under hypoxic condition, demonstrating that m6A pathway is an important regulator during hypoxic response. Collectively, our studies indicate that crosstalk between m6A and HIF1 pathway is essential for cellular response to hypoxia, providing insights into the underlying molecular mechanisms during hypoxia.

LXRα agonists have attracted significant attention due to their potential biological activities on promoting cholesterol efflux. This study was designed to investigate whether setosphapyrone C and D have potential lipid-lowering capacity and the underlying mechanisms in vitro. Our data showed that setosphapyrone C and D had weak cytotoxicity compared to the liver X receptor α (LXRα) agonist T0901317. In RAW 264.7 macrophages, setosphapyrone C and D significantly enhanced [3H]-cholesterol efflux by ~ 21.3% and 32.4%, respectively; furthermore, setosphapyrone C and D enhanced the protein levels of ATP-binding cassette transporter (ABC) A1 and LXRα by 58% and 69%, and 60% and 70% (8 µM), respectively; however, they had no effect on the protein levels of ABCG1 and scavenger receptor B type 1; additionally, they had minor effect on the mRNA expression of lipogenic genes. Of note, setosphapyrone C and D significantly enhanced LXRα/ABCA1pathway in mice primary macrophages. In BRL cells, setosphapyrone C and D significantly improved the protein levels of ABCA1 and ABCG1; setosphapyrone D significantly enhanced the protein expression of low-density lipoprotein. Collectively, setosphapyrone C and D with weak cytotoxicity exhibited effective lipid-lowering effect via enhancing LXRα/ABC pathways. Setosphapyrones possess potential application for the treatment of hyperlipidemic diseases.

RNase J is a prokaryotic 5′-3′ exo/endoribonuclease that functions in mRNA decay and rRNA maturation. Here, we report a novel duplex unwinding activity of mpy-RNase J, an archaeal RNase J from Methanolobus psychrophilus, which enables it to degrade duplex RNAs with hairpins up to 40 bp when linking a 5′ single-stranded overhangs of ≥ 7 nt, corresponding to the RNA channel length. A 6-nt RNA-mpy-RNase J-S247A structure reveals the RNA-interacting residues and a steric barrier at the RNA channel entrance comprising two archaeal loops and two helices. Mutagenesis of the residues key to either exoribonucleolysis or RNA translocation diminished the duplex unwinding activity. Substitution of the residues in the steric barrier yielded stalled degradation intermediates at the duplex RNA regions. Thus, an exoribonucleolysis-driven and steric occlusion-based duplex unwinding mechanism was identified. The duplex unwinding activity confers mpy-RNase J the capability of degrading highly structured RNAs, including the bacterial REP RNA, and archaeal mRNAs, rRNAs, tRNAs, SRPs, RNase P and CD-box RNAs, providing an indicative of the potential key roles of mpy-RNase J in pleiotropic RNA metabolisms. Hydrolysis-coupled duplex unwinding activity was also detected in a bacterial RNase J, which may use a shared but slightly different unwinding mechanism from archaeal RNase Js, indicating that duplex unwinding is a common property of the prokaryotic RNase Js.

Background Shanzhuyu (the dried mature sarcocarp of Cornus officinalis Sieb. et Zucc., DMSCO) is a Chinese herb that can be used for the treatment of Alzheimer’s disease (AD), but its mechanism remains unknown. The present study aimed to investigate the active ingredients and effective mechanisms of DMSCO for the treatment of AD based on a network pharmacology approach. Methods The active components of DMSCO were collected from the TCMSP and ETCM databases and the target proteins of these compounds were predicted using TCMSP, SwissTargetPrediction and the STITCH database. The AD-related target proteins were identified from the OMIM, DisGeNet, GEO and GeneCards databases. The network interaction model of the compound-target-disease was established and was used to obtain the key targets of DMSCO on AD through network topology analysis. Subsequently, gene enrichment in Gene Ontology (GO) and KEGG pathways were conducted using the David 6.8 online tool. Results A total of 30 DMSCO effective compounds and 209 effective drug targets were obtained. A total of 172 AD-related genes and 37 shared targets of DMSCO and AD were identified. A total of 43 key targets for the treatment of AD were obtained from the topological analysis of the DMSCO-AD target network. These key targets were involved in a variety of biological processes, including amyloid deposition, apoptosis, autophagy, inflammatory response and oxidative stress and pathways, such as the PI3K-AKT, MAPK and TNF pathways. Three key compounds, namely ursolic acid, anethole and β-sitosterol were obtained from the analysis of the key targets. Conclusions Ursolic acid, anethole and β-sitosterol may be the main active components of DMSCO in the treatment of AD. DMSCO can treat AD by regulating amyloid deposition, apoptosis, autophagy, inflammatory response and oxidative stress via the PI3K-AKT, MAPK and other signaling pathways.

Light-emitting diodes (LEDs) have been developed as light sources for indoor algae cultivation. In this study, we determined the effects of blue and red light ratios on weight gain, pigment content, antioxidant activity, and phytoene desaturase (PDS) gene expression in Caulerpa lentillifera. Caulerpa lentillifera was grown under six LED light treatments: white (W), red (R, 660 nm, 100%), blue (B, 447 nm, 100%), 1B1R (50% blue + 50% red), 1B2R (33.3% blue + 66.7% red), and 1B5R (16.7% blue + 83.3% red). Our results showed that red light improved the weight gain percentage of C. lentillifera, whereas red light with a low proportion of blue light (1B5R, 16.7%; blue + 83.3% red) led to a significantly higher weight gain percentage and photosynthetic pigment (Chl a + Chl b) content than the other LED light treatments. Increasing the proportion of blue light negatively affected weight gain and the photosynthetic pigment contents. However, blue LED light induced significantly higher transcription of the PDS gene, which coincided with increased β-carotene accumulation and antioxidant activity in C. lentillifera. These results indicated that the ratio of blue to red light is important for the indoor cultivation of C. lentillifera, and 100 μmol photons m−2 s−1 of 1B5R LED light with a 12/12 h light-dark photoperiod resulted in good growth and development.

Ganoderma mushrooms have been widely used as functional food in China, Japan, and Korea. Ganoderma triterpenoids are deemed to be the main functional constituents. The structures of Ganoderma triterpenoids are complex but quite similar, which makes their analyses markedly limited. In this study, we developed a general 2D NMR method to differentiate Ganoderma triterpenoids, which classifies them into six types (A-F). Then, by the NMR-based isolation of A-F type triterpenoids from the fruiting bodies of G. resinaceum, four new compounds (1-4) and eight known compounds (5-12) were obtained. Moreover, combined with spiking experiments in 1D and 2D NMR spectra, compounds 5, 7, and 8, which belong to triterpenoids of A and B types, were identified. At the end, to achieve a more extensive application for this NMR method, a qNMR method for the absolute quantification of 5, 7, and 8 in the gross triterpenoids from G. resinaceum was set up. The results showed that this NMR method is reliable for the NMR-guided isolation and quantification of triterpenoids in G. resinaceum.

Universal stress proteins (Usps) exist ubiquitously in bacteria and other organisms. Usps play an important role in adaptation of bacteria to a variety of environmental stresses. There is increasing evidence that Usps facilitate pathogens to adapt host environment and are involved in pathogenicity. Edwardsiella piscicida (formerly included in E. tarda) is a severe fish pathogen and infects various important economic fish including tilapia (Oreochromis niloticus). In E. piscicida, a number of systems and factors that are involved in stress resistance and pathogenesis were identified. However, the function of Usps in E. piscicida is totally unknown. In this study, we examined the expressions of 13 usp genes in E. piscicida and found that most of these usp genes were up-regulated expression under high temperature, oxidative stress, acid stress, and host serum stress. Particularly, among these usp genes, usp13, exhibited dramatically high expression level upon several stress conditions. To investigate the biological role of usp13, a markerless usp13 in-frame mutant strain, TX01Δusp13, was constructed. Compared to the wild type TX01, TX01Δusp13 exhibited markedly compromised tolerance to high temperature, hydrogen peroxide, and low pH. Deletion of usp13 significantly retarded bacterial biofilm growth and decreased resistance against serum killing. Pathogenicity analysis showed that the inactivation of usp13 significantly impaired the ability of E. piscicida to invade into host cell and infect host tissue. Introduction of a trans-expressed usp13 gene restored the lost virulence of TX01Δusp13. In support of these results, host immune response induced by TX01 and TX01Δusp13 was examined, and the results showed reactive oxygen species (ROS) levels in TX01Δusp13-infected macrophages were significantly higher than those in TX01-infected cells. The expression level of several cytokines (IL-6, IL-8, IL-10, TNF-α, and CC2) in TX01Δusp13-infected fish was significantly higher than that in TX01-infected fish. These results suggested that the deletion of usp13 attenuated the ability of bacteria to overcome the host immune response to pathogen infection. Taken together, our study indicated Usp13 of E. piscicida was not only important participant in adversity resistance, but also was essential for E. piscicida pathogenicity and contributed to block host immune response to pathogen infection.

Background In cereal crop rice, auxin is known as an important class of plant hormone that regulates a plethora of plant growth and development. Glycosylation of auxin is known to be one of the important mechanisms mediating auxin homeostasis. However, the relevant auxin glucosyltransferase (GT) in rice still remains largely unknown. Results In this study, using known auxin glucosyltransferases from other species as queries, twelve putative auxin UDP-glycosyltransferase (UGT) genes were cloned from rice and the one showing highest sequence similarity, named as OsIAGT1, was expressed as recombinant protein. In vitro enzymatic analysis showed that recombinant OsIAGT1 was capable of catalyzing glucosylation of IAA, IBA and other auxin analogs, and that OsIAGT1 is quite tolerant to a broad range of reaction conditions with peak activity at 30 °С and pH 8.0. OsIAGT1 showed favorite activity towards native auxins over artificially synthesized ones. Further study indicated that expression of OsIAGT1 can be upregulated by auxin in rice, and with OsIAGT1 overexpressing lines we confirmed that OsIAGT1 is indeed able to glucosylate IAA in vivo. Consistently, ectopic expression of OsIAGT1 leads to declined endogenous IAA content, as well as upregulated auxin synthesis genes and reduced expression of auxin-responsive genes, which likely leads to the reduced plant stature and root length in OsIAGT1 overexpression lines. Conclusion Our result indicated that OsIAGT1 plays an important role in mediating auxin homeostasis by catalyzing auxin glucosylation, and by which OsIAGT1 regulates growth and development in rice.

Background The intestinal polyp is the precancerous lesion of colorectal cancer. DNA methylation and intestinal microbiota may play an important role in the development of intestinal polyp. Materials and methods In this study, we included 10 patients with intestinal polyps who received the colonoscopy examination. We applied the Illumina Human Methylation 850K array to investigate the epigenome-wide DNA methylation patterns. Then, we filtered out the hub genes in the protein-protein interaction networks using functional epigenetic modules analysis. We also analyzed the colonizing bacteria on the surface of polyps compared with those in normal colonic mucosal epithelium with 16S ribosomal DNA sequencing. Results We identified 323 hypermethylated sites and 7992 hypomethylated sites between intestinal polyps and normal samples. Five hub genes, including CREB1, LPA, SVIL and KRT18, were identified in five modules. Hypomethylation of CREB1 is a candidate marker of colorectal adenoma. Gut microbiota analysis showed that Butyricicoccus was significantly decreased in the intestinal polyp groups. Conclusion In conclusion, we identified DNA methylation disparities in intestinal polyps compared with normal tissue, of which methylation of CREB1 may hold clinical significance in colorectal cancer progress. Colonizing bacteria in the colonic epithelium might be related to the formation of intestinal polyps.

Two types of tonoplast proton pumps, H+ -pyrophosphatase (V-PPase) and the H+ -ATPase (V-ATPase), establish the proton gradient that powers molecular traffic across the tonoplast thereby facilitating turgor regulation and nutrient homeostasis. However, how proton pumps regulate development remains unclear. In this study, we investigated the function of two types of proton pumps in Arabidopsis embryo development and pattern formation. While disruption of either V-PPase or V-ATPase had no obvious effect on plant embryo development, knocking out both resulted in severe defects in embryo pattern formation from the early stage. While the first division in wild-type zygote was asymmetrical, a nearly symmetrical division occurred in the mutant, followed by abnormal pattern formation at all stages of embryo development. The embryonic defects were accompanied by dramatic differences in vacuole morphology and distribution, as well as disturbed localisation of PIN1. The development of mutant cotyledons and root, and the auxin response of mutant seedlings supported the hypothesis that mutants lacking tonoplast proton pumps were defective in auxin transport and distribution. Taking together, we proposed that two tonoplast proton pumps are required for vacuole morphology and PIN1 localisation, thereby controlling vacuole and auxin-related developmental processes in Arabidopsis embryos and seedlings.

Edwardsiella piscicida is a severe fish pathogen. Haem utilization systems play an important role in bacterial adversity adaptation and pathogenicity. In this study, a speculative haem utilization protein, HutZEp, was characterized in E. piscicida. hutZEp is encoded with two other genes, hutW and hutX, in an operon that is similar to the haem utilization operon hutWXZ identified in V. cholerae. However, protein activity analysis showed that HutZEp is probably not related to hemin utilization. To explore the biological role of HutZEp, a markerless hutZEp in-frame mutant strain, TX01ΔhutZ, was constructed. Deletion of hutZEp did not significantly affect bacterial growth in normal medium, in iron-deficient conditions, or in the presence of haem but significantly retarded bacterial biofilm growth. The expression of known genes related to biofilm growth was not affected by hutZEp deletion, which indicated that HutZEp was probably a novel factor promoting biofilm formation in E. piscicida. Compared to the wild-type TX01, TX01ΔhutZ exhibited markedly compromised tolerance to acid stress and host serum stress. Pathogenicity analysis showed that inactivation of hutZEp significantly impaired the ability of E. piscicida to invade and reproduce in host cells and to infect host tissue. In contrast to TX01, TX01ΔhutZ was defective in blocking host macrophage activation. The expression of hutZEp was directly regulated by the ferric uptake regulator Fur. This study is the first functional characterization of HutZ in a fish pathogen, and these findings suggested that HutZEp is essential for E. piscicida biofilm formation and contributes to host infection.

Fomitopsis pinicola (Sw. Ex Fr.) Krast has been commonly used as a health food source and antitumor agent. To uncover bioactive key composition of F. pinicola, in our study, we investigated the chemical constituents of a methanol extract of F. pinicola and thirty-five lanostane-type tritetpenoids; 13 new compounds (1-13) and twenty-two known analogues (14-35) were isolated. Among them, compounds 1-9 were C30 lanostane triterpenoids and triterpene sugar esters, while compounds 10-13 were C31 triterpenoids and triterpene sugar esters. Their structures and absolute configurations were elucidated by extensive 1D, 2D NMR, MS, and IR spectra. Furthermore, cytotoxic activities of all isolates against five human tumor cell lines (HL-60, A549, SMMC-7721, MCF-7, and SW480) were evaluated. The results showed that compounds 12, 14, 17, 18, 22, and 23 displayed cytotoxic effects against five human tumor cell lines with IC50 values ranging from 3.92-28.51 μM. Meanwhile, compounds 9 and 35 exhibited selected inhibitory activities against HL-60, SMMC-7721, and MCF-7 with IC50 values in the range of 13.57-36.01 μM. Furthermore, the flow cytometry analysis revealed that compounds 17, 22, and 35 induced apoptosis in HL-60 cell lines. Their structure-activity relationships were preliminarily reported. These findings indicate the vital role of triterpenoids and their glycosides in explaining antitumor effects of F. pinicola and provide important evidence for further development and utilization of this fungus.

KANK proteins mediate cross-talk between dynamic microtubules and integrin-based adhesions to the extracellular matrix. KANKs interact with the integrin/actin-binding protein talin and with several components of microtubule-stabilizing cortical complexes. Because of actomyosin contractility, the talin-KANK complex is likely under mechanical force, and its mechanical stability is expected to be a critical determinant of KANK recruitment to focal adhesions. Here, we quantified the lifetime of the complex of the talin rod domain R7 and the KN domain of KANK1 under shear-force geometry and found that it can withstand forces for seconds to minutes over a physiological force range up to 10 pN. Complex stability measurements combined with cell biological experiments suggest that shear-force stretching promotes KANK1 localization to the periphery of focal adhesions. These results indicate that the talin-KANK1 complex is mechanically strong, enabling it to support the cross-talk between microtubule and actin cytoskeleton at focal adhesions.

The gut microbiota of infants changes over time and is affected by various factors during early life. However, rarely have studies explored the gut microbiota development and affecting factors in the Chinese infant population. We enrolled 102 infants and collected stool samples from them at birth, 42 days, 3 mo, and 6 mo after delivery to characterize the microbiota signatures and the effects of different factors that modulate the gut microbiota diversity, composition, and function over time. DNA extracted from the bacteria in the stool samples was subjected to high-throughput sequencing and bioinformatics analysis. Microbial richness and diversity increased significantly during the first 6 mo of life. Beneficial microbes such as Bifidobacterium, Lactobacillus, and Blautia were found to be increased in the infant’s gut at 6 mo, while pathological bacteria such as Escherichia-Shigella, Enterobacter, Staphylococcus, and Klebsiella decreased over time. The changes in the infant delivery mode and infant-feeding mode only produced changes in the microbial composition, whereas changes in bacterial richness, diversity and effects sizes on the microbial architecture were all time dependent. A comparison of infant delivery modes conveyed a decrease in abundance of Bacteroidetes over time in the gut of infants born via C-section, while the Bifidobacterium was the most dominant genus in the vaginal delivery group. The gut microbiota of infants changed extensively during the first 6 mo of life. Delivery and feeding modes were strong factors that significantly affected microbial architecture and functions.

Endotoxin in water affects water quality and human health. Detecting endotoxin in water required sensitive, accurate and stable methods due to the large amounts of interferences and highly varied endotoxin levels in different water. For the first time, a novel nanobiocomposite sandwich immunosensor was fabricated for accurate and convenient endotoxin determination by using molecularly imprinted nano-membrane (MIM) and nature antibody selective to different epitopes of endotoxin as affinity molecules simultaneously. Endotoxin-imprinted MIM was prepared on the surface of microplate by dopamine self-polymerization method. MIM enriched endotoxin by binding polysaccharides selectively. Then primary antibody specific to lipid A of endotoxin quantified the endotoxin captured by MIM. Using the high stability of MIM to harsh conditions and the high accuracy of nature antibody as affinity molecules simultaneously, selective sample pre-treatment was designed into immunosensor effectively. The achieved immunosensor detected endotoxin in different diluted or un-diluted water sensitively and accurately. The LOD, LOQ and linearity of the immunosensor were 4 × 10−6 μg/L, 1.3 × 10-5 μg/L and 10-5-105 μg/L respectively. While only proper diluted water samples could be accurately detected by limulus amebocyte lysate assays (LAL). The immunosensor also had much higher sensitivity and accuracy than indirect competitive ELISA which used the same primary antibody. By combing sample pre-treatment with immunosensor, the nanobiocomposite sandwich immunosensor provides a solution to detect endotoxin in water accurately and conveniently.

Transmembrane chemoreceptors are widely present in Bacteria and Archaea. They play a critical role in sensing various signals outside and transmitting to the cell interior. Here, we report the structure of the periplasmic ligand-binding domain (LBD) of the transmembrane chemoreceptor MCP2201, which governs chemotaxis to citrate and other organic compounds in Comamonas testosteroni. The apo-form LBD crystal revealed a typical four-helix bundle homodimer, similar to previously well-studied chemoreceptors such as Tar and Tsr of Escherichia coli. However, the citrate-bound LBD revealed a four-helix bundle homotrimer that had not been observed in bacterial chemoreceptor LBDs. This homotrimer was further confirmed with size-exclusion chromatography, analytical ultracentrifugation and cross-linking experiments. The physiological importance of the homotrimer for chemotaxis was demonstrated with site-directed mutations of key amino acid residues in C. testosteroni mutants.

Lymph node metastasis is an important step in the progression of colorectal cancer (CRC); however, the underlying mechanisms are still unknown. The aim of the present study was to identify the gene expression pattern during lymph node metastasis in CRC and to identify upstream microRNAs (miRNAs) to explore the underlying mechanisms in detail. A total of 305 differently expressed genes (DEGs) were identified, including 227 upregulated genes and 78 downregulated genes in lymph node metastasis. Pathway and process enrichment analysis demonstrated that DEGs were significantly enriched in 'NABA CORE MATRISOME', 'extracellular matrix assembly', 'antimicrobial humoral response' and 'Toll-like receptor signaling' pathways. The top 10 hub genes were identified by protein-protein interaction network, and sub-networks revealed that these genes were involved in significant pathways, including 'neutrophil chemotaxis' and 'Smooth Muscle Contraction'. In addition, 73 mature differently expressed miRNAs associated with lymph node metastasis were identified, of which 48 were upregulated and 25 were downregulated. Six miRNAs were identified to regulate DEGs. Additionally, based on the relationship between miRNAs and transcription factors, a miRNA-TF-mRNA network was constructed. In conclusion, DEGs, miRNAs and their interactions and pathways were identified in lymph node metastasis in CRC, which provided insight into the mechanism of CRC metastasis and may be used to develop novel targets for CRC treatment.

Plant systemic acquired resistance (SAR) provides an efficient broad-spectrum immune response to pathogens. SAR involves mobile signal molecules that are generated by infected tissues and transported to systemic tissues. Methyl salicylate (MeSA), a molecule that can be converted to salicylic acid (SA), is an essential signal for establishing SAR, particularly under a short period of exposure to light after pathogen infection. Thus, the control of MeSA homeostasis is important for an optimal SAR response. Here, we characterized a uridine diphosphate-glycosyltransferase, UGT71C3, in Arabidopsis (Arabidopsis thaliana), which was induced mainly in leaf tissue by pathogens including Pst DC3000/avrRpt2 (Pseudomonas syringae pv tomato strain DC3000 expressing avrRpt2). Biochemical analysis indicated that UGT71C3 exhibited strong enzymatic activity toward MeSA to form MeSA glucosides in vitro and in vivo. After primary pathogen infection by Pst DC3000/avrRpt2, ugt71c3 knockout mutants exhibited more powerful systemic resistance to secondary pathogen infection than that of wild-type plants, whereas systemic resistance in UGT71C3 overexpression lines was compromised. In agreement, after primary infection of local leaves, ugt71c3 knockout mutants accumulated significantly more systemic MeSA and SA than that in wild-type plants. whereas UGT71C3 overexpression lines accumulated less. Our results suggest that MeSA glucosylation by UGT71C3 facilitates negative regulation of the SAR response by modulating homeostasis of MeSA and SA. This study unveils further SAR regulation mechanisms and highlights the role of glucosylation of MeSA and potentially other systemic signals in negatively modulating plant systemic defense.

Harmful algal blooms (HABs) have adverse effects on the marine ecological environment, public health, and marine economy. Thus, methods for the accurate and rapid identification of harmful algal species are urgently needed for the effective monitoring of the occurrence of HABS. A method for the parallel detection of harmful algal species must be established because various HAB-forming algal species coexist in the marine environment. This work developed a multiplex PCR (mPCR) method that can simultaneously detect six common HAB-forming microalgal species distributed along the coast of China: Karlodinium veneficum (Kv), Chattonella marina (Cm), Skeletonema spp., Scrippsiella trochoidea (St), Karenia mikimotoi (Km), and Prorocentrum donghaiense (Pd). Specific mPCR primers were designed from the internal transcribed spacer rDNA or large subunit rDNA gene of the target algal species. The mPCR conditions were optimized. Each mPCR primer was subjected to a cross-reactivity test with other microalgae to confirm the specificity of the developed mPCR system. The results of the system stability test indicated that the background concentration of DNA tested did not affect the performance of the established mPCR system. The results of the sensitivity test showed that the detection limit of the proposed mPCR system for Kv, Cm, Km, and Pd was 0.6 ng μL-1 and that for Skeletonema spp. and St was 0.06 ng μL-1. Additional mPCR analysis with spiked field samples revealed that the detection limit of the mPCR system for Km, Pd, and Kv was 60 cells, whereas that for Cm, Skeletonema spp., and St was 6 cells. The convenience and accuracy of the established mPCR assay were further validated through tests with field samples. The proposed mPCR assay is characterized by parallel analysis, strong specificity, and stability and can be used to supplement morphology-based detection methods for algal species.

L,D-transpeptidases, widely distributed in bacteria and even in the difficult-to-treat ESKAPE pathogens, can confer antibacterial resistance against the traditional β-lactam antibiotics through bypass of the 4 → 3 transpeptide linkage. LdtMt2, a l , d -transpeptidase in Mycobacteria tuberculosis, is essential for bacterial virulence and is considered as a potential anti-tuberculosis target inhibited by carbapenems. Diverse interaction modes between carbapenems and LdtMt2 have been reported, there are only limited evidences to validate those interaction modes. Herein, we identified the stable binding states of two carbapenems, imipenem and ertapenem, via crystallographic and biochemical studies, discovered that they adopt similar binding conformations. We further demonstrate the absence of the 1-β-methyl group in imipenem and the presence of both Y308 and Y318 residues in LdtMt2 synergistically resulted in one order of magnitude higher affinity for imipenem than ertapenem. Our study provides a structural basis for the rational drug design and evolvement of novel carbapenems against bacterial L,D-transpeptidases.

Phenolics are a class of plant secondary metabolites that play important roles in plant growth and environmental adaptation. Glucosylation of phenolics is one of the molecular mechanisms controlling phenolics homeostasis. However, the relevant glucosyltransferases are largely unknown. In this study, a putative family 1 glucosyltransferase gene OsSGT1 was cloned from rice due to its close homology with the previously reported phenolics-related glucosyltransferases UGT84A1-A4, and the phylogenetic relationship of OsSGT1 with homologs from other species was investigated. Recombinant OsSGT1 protein showed strong activity towards phenolics to form their glucose conjugates. This is the first identified natural phenolics-related glucosyltransferase in rice. In addition, the expression patterns of OsSGT1 in different tissues of rice indicated that OsSGT1 was predominantly expressed in the old leaves and dough grains, suggesting that OsSGT1 might be involved in the maturation process of rice by regulating phenolic metabolism, and thus deepened our understanding on the roles of phenolics in rice growth and environmental adaptation.

Glypican-1 (GPC1), a cell-surface heparan sulfate proteoglycan, promotes the pathogenesis of many human cancers. This study focuses on the role of GPC1 in the promotion of cell proliferation and motility in esophageal squamous cell carcinoma (ESCC). The expression and distribution of GPC1 were measured in tumor tissues from 248 ESCC patients using immunohistochemical (IHC) assays. Cell counting (kit-8), flow cytometry, Transwell, wound healing, IHC, and Western blotting assays were performed to examine the molecular mechanisms that underlie how GPC1 enhances cell proliferation and motility. The level of GPC1 was higher in ESCC tumor samples than in para-tumor tissues (IHC score: 5.42 ± 2.15 vs. 0.86 ± 0.96). Ectopic overexpression of GPC1 in EC9706 cells promoted cell growth and the G1/S phase transition; conversely, GPC1 knockdown in Eca109 cells attenuated cell proliferation and induced G2/M phase arrest. In addition, GPC1 upregulation enhanced ESCC cell motility and induced epithelial mesenchymal transition (EMT), as demonstrated by the aberrant expression of EMT markers. Mechanistically, we demonstrated that GPC1 increased levels of p-Akt and β-catenin and reduced PTEN expression in ESCC. Our study indicated that GPC1 promotes the aggressive proliferation of ESCC cells by regulating the PTEN/Akt/β-catenin pathway. GPC1 may be a promising target for ESCC treatment.

A high-quality X-ray crystal structure reveals the mechanism of compound 1a inhibiting SIRT2 deacetylase and decanoylase. Structure–activity relationship (SAR) analysis of the synthesized derivatives of 1a reveals the high requirements needed for selective inhibitors to bind with the induced hydrophobic pocket and potently inhibit sirtuin 2 deacetylase.

Aggregation-induced emission luminogens (AIEgens) with a definite structure–activity relationship play important roles in site-specific bio-imaging and applications. However, the lack of a clear structure–activity relationship for the excited-state intramolecular proton transfer (ESIPT) molecules, which are a series of powerful AIEgens, restricts their biological applications. Herein, the cell-penetrating capability of 4-N,N-dimethylaminoaniline salicylaldehyde Schiff-bases (DSS) with different substituents was investigated. The diethylamino functionalized ESIPT Schiff base (DSS-4-DEA) displayed high cell-penetrating capacity, making this simple AIEgen turn into a more powerful fluorescent functional material in biosystems. The DSS-4-DEA was successfully used for a fluorescence assay of the intracellular Cu2+. Besides, the DSS-4-DEA could also be used as an efficient transmembrane carrier to drastically enhance the internalization of DSS-5-Cl to achieve two-color imaging. In addition, the DSS-4-DEA could be used to improve the transportation of anticancer drug curcumin (Cur) into HeLa cells, leading to increased apoptosis. The complete exploration of the structure–activity relationship of ESIPT molecules might supply lots of new applications of AIE materials in biological systems.

The transgenic rice line T1C-19 provides high resistance to lepidopteran pests because of the synthesis of the Bacillus thuringiensis (Bt) insecticidal protein Cry1C. It thus shows good prospect for commercial planting in China. Species of Cladocera, an order of aquatic arthropods commonly found in aquatic ecosystems such as rice paddies, might be exposed to the insecticidal protein released from Bt-transgenic rice-straw residues. For the study reported herein, we used Daphnia magna (water flea) as a representative of Cladocera to evaluate whether aquatic arthropods are adversely affected when exposed to Bt rice-straw leachates. We exposed D. magna to M4 medium containing various volume percentages of medium that had been incubated with T1C-19 rice straw or rice straw from its non-transformed near-isoline Minghui 63 (MH63) for 21 days. Compared with pure M4 medium (control), the fitness and developmental and reproduction parameters of D. magna decreased significantly when exposed to rice-straw leachates; conversely, no significant differences between the T1C-19 and MH63 rice-straw leachate treatments were observed, indicating that the Bt rice straw leachate did not adversely affect this non-target species.

Atherosclerosis is a chronic disease starting with the entry of monocytes into the subendothelium and the subsequent differentiation into macrophages. Macrophages are the major immune cells in atherosclerotic plaques and are involved in the dynamic progression of atherosclerotic plaques. The biological properties of atherosclerotic plaque macrophages determine lesion size, composition, and stability. The heterogenicity and plasticity of atherosclerotic macrophages have been a hotspot in recent years. Studies demonstrated that lipids, cytokines, chemokines, and other molecules in the atherosclerotic plaque microenvironment regulate macrophage phenotype, contributing to the switch of macrophages toward a pro- or anti-atherosclerosis state. Of note, M1/M2 classification is oversimplified and only represent two extreme states of macrophages. Moreover, M2 macrophages in atherosclerosis are not always protective. Understanding the phenotypic diversity and functions of macrophages can disclose their roles in atherosclerotic plaques. Given that lipid-lowering therapy cannot completely retard the progression of atherosclerosis, macrophages with high heterogeneity and plasticity raise the hope for atherosclerosis regression. This review will focus on the macrophage phenotypic diversity, its role in the progression of the dynamic atherosclerotic plaque, and finally discuss the possibility of treating atherosclerosis by targeting macrophage microenvironment.

Caseinate was crosslinked by horseradish peroxidase (HRP) or microbial transglutaminase (TGase) and mixed with kaempferol and quercetin at 293–313 K (i.e. 20–40 °C), respectively. Generally, these two polyphenols dose-dependently induced fluorescent quenching in caseinate or its crosslinked products via a static mechanism, while enzymatic crosslinking endowed caseinate with higher affinity for the polyphenols with increased apparent binding constants [(9.94–168.77) × 105 versus (4.92–6.53) × 105 L/mol], unchanged binding site number and slightly shortened binding distance. To form protein–polyphenol complexes, hydrophobic force was the main driving force for the HRP-crosslinked caseinate and unreacted caseinate, while hydrogen-bonds and van der Waals force were the main driving forces for the TGase-crosslinked caseinate. Overall, quercetin was more potent than kaempferol to bind to the proteins, while TGase-mediated caseinate crosslinking induced the highest affinity to the polyphenols with the largest ΔG decrease. Thus, two types of crosslinking impacted the driving forces, apparent binding constant and thermodynamic indices of caseinate-polyphenol interaction.

Antibiotics, a common strategy used for neonatal infection, show consistent effect on the gut microbiota of neonates. Supplementation with probiotics has become increasingly popular in mitigating the loss of the gut microbiota. However, no clear consensus recommending the use of probiotics in the infection of neonates currently exists. This study examined the effects of probiotics on the gut microbiota of infectious neonates when used concurrently with or during the recovery period following antibiotic therapy. Fifty-five full-term neonates diagnosed with neonatal infections were divided into the following groups: NI (no intervention, antibiotic therapy only), PCA (probiotics used concurrently with antibiotics), and PAA (probiotics used after antibiotics). The NI group received antibiotic treatment (piperacillin–tazobactam) for 1 week and the PCA group received antibiotic treatment together with probiotics (Bifidobacterium longum, Lactobacillus acidophilus, and Enterococcus faecalis) for 1 week. The PAA group received antibiotic treatment for 1 week followed by probiotics for 1 week. Fecal samples were collected at four time nodes: newborn, 1 week, 2 weeks, and 42 days after birth. The composition of the gut microbiota was determined by the high-throughput sequencing of 16S rRNA amplicons. Antibiotic exposure was found to dramatically alter gut microbiota, with a significant decrease of Bifidobacterium and Lactobacillus. The use of probiotics did not restore the overall diversity of the gut microbiota. However, using probiotics simultaneously with the antibiotics was found to be beneficial for the gut microbiota as compared to delaying the use of probiotics to follow treatment with antibiotics, particularly in promoting the abundance of Bifidobacterium. These results suggest that the early use of probiotics may have a potential ability to remodel the gut microbiota during recovery from antibiotic treatment. However, further study is required to fully understand the long-term effects including the clinical benefits.

BackgroundSexual dimorphism is widespread in insects. The certain specialized structures may be used as weapons in male–male combats or as ornaments to enhance mating opportunities.ResultsWe report striking swollen first tarsal segments in two families, four genera and six species of scorpionflies from the Middle Jurassic Yanliao Biota of Northeastern China. Swollen tarsal segments are restricted to male specimens and to hind leg tarsi. The geometric morphometric analyses reveal that the degree of swelling within the orthophlebiid species possessing swollen first metatarsal segments is species-specific, which can be used as a diagnostic character for taxonomic and phylogenetic studies.ConclusionsThe new findings indicate that swollen first metatarsal segments are relatively common in the family Orthophlebiidae during the Middle Jurassic. The tarsal swellings are considered to be sexually dimorphic, potentially associated with sexually display by males and/or camouflage of a “nuptial gift” in the mating process.

Concentrations of 29 elements were analyzed in the marginal area and central area of the shell nacreous layer of the winged pearl oyster Pteria penguin using a laser ablation inductively coupled plasma mass spectrometer. Color of the two shell areas was determined using the color parameter values of lightness, greenness/redness, and blueness/yellowness. It is shown that the concentrations of the elements and the nacreous color are different in the marginal area and central area. The concentrations of Mg, P, B, Li, Cu, and Mo are significantly correlated with lightness and differently distributed in the two shell areas (P < 0.05). The concentration of Na and Mg is significantly related to greenness/redness and differently distributed in the two shell areas (P < 0.05). The concentration of Na, Mg, P, B, Li, and Mo is significantly related to blueness/yellowness and differently distributed in the two shell areas (P < 0.05). The concentration of Mg significantly related to lightness, greenness/redness, and blueness/ yellowness and differently distributed in the two shell areas (P < 0.05). This study provides a new perspective to illustrate the mechanism of color change between the marginal and central areas.