Blocking Osa-miR1871 enhances rice resistance against Magnaporthe oryzae and yield.

MicroRNAs (miRNAs) play vital roles in plant development and defence responses against various stresses. Here, we show that blocking miR1871 improves rice resistance against Magnaporthe oryzae and enhances grain yield simultaneously. The transgenic lines overexpressing miR1871 (OX1871) exhibit compromised resistance, suppressed defence responses and reduced panicle number resulting in slightly decreased yield. In contrast, the transgenic lines blocking miR1871 (MIM1871) show improved resistance, enhanced defence responses and significantly increased panicle number leading to enhanced yield per plant. The RNA-seq assay and defence response assays reveal that blocking miR1871 resulted in the enhancement of PAMP-triggered immunity (PTI). Intriguingly, miR1871 suppresses the expression of LOC_Os06g22850, which encodes a microfibrillar-associated protein (MFAP1) locating nearby the cell wall and positively regulating PTI responses. The mutants of MFAP1 resemble the phenotype of OX1871. Conversely, the transgenic lines overexpressing MFAP1 (OXMFAP1) or overexpressing both MFAP1 and miR1871 (OXMFAP1/OX1871) resemble the resistance of MIM1871. The time-course experiment data reveal that the expression of miR1871 and MFAP1 in rice leaves, panicles and basal internode is dynamic during the whole growth period to manipulate the resistance and yield traits. Our results suggest that miR1871 regulates rice yield and immunity via MFAP1, and the miR8171-MFAP1 module could be used in rice breeding to improve both immunity and yield.

Osa-miR160a confers broad-spectrum resistance to fungal and bacterial pathogens in rice.

Rice production is threatened by multiple pathogens. Breeding cultivars with broad-spectrum disease resistance is necessary to maintain and improve crop production. Previously we found that overexpression of miR160a enhanced rice blast disease resistance. However, it is unclear whether miR160a also regulates resistance against other pathogens, and what the downstream signaling pathways are. Here, we demonstrate that miR160a positively regulates broad-spectrum resistance against the causative agents of blast, leaf blight and sheath blight in rice. Mutations of miR160a-targeted Auxin Response Factors result in different alteration of resistance conferred by miR160a. miR160a enhances disease resistance partially by suppressing ARF8, as mutation of ARF8 in MIM160 background partially restores the compromised resistance resulting from MIM160. ARF8 protein binds directly to the promoter and suppresses the expression of WRKY45, which acts as a positive regulator of rice immunity. Mutation of WRKY45 compromises the enhanced blast resistance and bacterial leaf blight resistance conferred by arf8 mutant. Overall, our results reveal that a microRNA coordinates rice broad-spectrum disease resistance by suppressing multiple target genes that play different roles in disease resistance, and uncover a new regulatory pathway mediated by the miR160a-ARF8 module. These findings provide new resources to potentially improve disease resistance for breeding in rice.

Integrated metabolomics and transcriptomics analysis reveals new biomarkers and mechanistic insights on atrazine exposures in MCF­7 cells.

Atrazine (ATZ) is a widely used herbicide worldwide and is a long-suspected endocrine-disrupting chemical. However, most endocrine-disrupting toxicity studies on ATZ have been based on animal models and those investigating inner mechanisms have only focused on a few genes. Therefore, the possible link between ATZ and endocrine-disrupting toxicity is still unclear. In this study, multi-omics and molecular biology techniques were used to elucidate the possible molecular mechanisms underlying the effect of ATZ exposure on MCF-7 proliferation at environmentally relevant concentrations. Our study is the first report on ATZ-induced one carbon pool by folate metabolic disorder in MCF-7 cells. A concentration of 1 µM ATZ yielded the highest cell viability and was selected for further mechanistic studies. A total of 34 significantly changed metabolites were identified based on metabolomic analysis, including vitamins, amino acids, fatty acids, and corresponding derivatives. Folate and pyridoxal have potential as biomarkers of ATZ exposure. One carbon pool by folate metabolic pathway was identified based on metabolic pathway analysis of the significantly altered pathways. Moreover, FTCD and MTHFD related to this pathway were further identified based on transcriptomic analysis and protein assays. Folate and different forms of 5,6,7,8-tetrahydrofolate, which participate in purine synthesis and associate with methyl groups (SOPC, arachidonic acid, and L-tryptophan) in one carbon pool by the folate metabolic pathway, potentially promote MCF-7 cell proliferation. These findings on the key metabolites and regulation of the related differentially expressed genes in folate metabolism will shed light on the mechanism of MCF-7 cell proliferation after ATZ exposure. Overall, this study provides new insights into the mechanistic understanding of toxicity caused by endocrine-disrupting chemicals.

RPW8.1 enhances the ethylene-signaling pathway to feedback-attenuate its mediated cell death and disease resistance in Arabidopsis.

The Arabidopsis RESISTANCE TO POWDERY MILDEW 8.1 (RPW8.1) activates confined cell death and defense against different pathogens. However, the underlying regulatory mechanisms still remain elusive. Here, we show that RPW8.1 activates ethylene signaling that, in turn, negatively regulates RPW8.1 expression. RPW8.1 binds and stabilizes 1-aminocyclopropane-1-carboxylate oxidase 4 (ACO4), which may in part explain increased ethylene production and signaling in RPW8.1-expressing plants. In return, ACO4 and other key components of ethylene signaling negatively regulate RPW8.1-mediated cell death and disease resistance via suppressing RPW8.1 expression. Loss of function in ACO4, EIN2, EIN3 EIL1, ERF6, ERF016 or ORA59 increases RPW8.1-mediated cell death and defense response. By contrast, overexpression of EIN3 abolishes or significantly compromises RPW8.1-mediated cell death and disease resistance. Furthermore, ERF6, ERF016 and ORA59 appear to act as trans-repressors of RPW8.1, with OAR59 being able to directly bind to the RPW8.1 promoter. Taken together, our results have revealed a feedback regulatory circuit connecting RPW8.1 and the ethylene-signaling pathway, in which RPW8.1 enhances ethylene signaling, and the latter, in return, negatively regulates RPW8.1-mediated cell death and defense response via suppressing RPW8.1 expression to attenuate its defense activity.

Influences of renal function descriptors on population pharmacokinetic modeling of vancomycin in Chinese adult patients.

Vancomycin, a glycopeptide antibiotic for the treatment of grampositive infections, is mainly eliminated via glomerular filtration. Thus, its therapeutic effects are affected predominantly by renal function. The aim of this study was to develop a population pharmacokinetic model of vancomycin for Chinese adult patients and to investigate the influence of different renal function descriptors on the predictability of the model. A retrospective analysis was performed based on the blood concentrations of vancomycin in 218 Chinese adult patients. Among these patients, the data from 160 were used to establish the population pharmacokinetic model, and the data from the remaining 58 patients were used for external model validation. A simulation was employed to determine the appropriate initial vancomycin dosage regimens in adult Chinese patients for reaching the target steady-state trough concentrations of 10-15 mg/L and 15-20 mg/L. We developed a one-compartment model with first-order absorption to characterize the concentration-time profile of vancomycin. There was a positive correlation between the body clearance of vancomycin and renal function; both creatinine clearance (CLCr) and age were the covariates that influenced the PK of vancomycin, and the excretion of vancomycin decreased as renal function diminishing with age. The typical clearance (CL) value was 2.829 L/h for 75-year-old patients with CLCr values of 80 mL/min, and the rate constant of CL with the CLCr changing at 1 mL/min was 0.00842. The influence coefficient of age on CL was 0.08143. The external validation results revealed that the current different descriptors of renal function behaved similarly to the predicted performance of the models. In conclusion, the developed model is appropriate for Bayesian dose predictions of vancomycin concentrations in the population of Chinese adult patients. Furthermore, the simulation provides a reference for clinical optimized antibacterial therapy with vancomycin.

Efficacy analysis of self-help position therapy after holmium laser lithotripsy via flexible ureteroscopy.

BACKGROUND: To observe the efficacy of self-help position therapy (SHPT) after holmium laser lithotripsy via flexible ureteroscopy (FURS). METHODS: From January 2010 to November 2015, 736 nephrolithiasis patients who had received FURS lithotripsy were analyzed retrospectively. In position group, 220 cases accepted SHPT after lithotripsies, and 428 cases as control, coming from another independent inpatient area in the same center. The stone-free status (SFS) between two groups were compared at the 2nd, 4th and 12th week ends by X-ray examinations. RESULTS: The preoperative incidence of hydronephrosis (25.9% vs. 18.0%, p = 0.018) or lower calyceal seeper (33.6% vs. 24.3%, p = 0.012) and the proportion of patients with > 2.0 cm stones (33.6% vs. 24.3%, p = 0.003) were all significantly higher in position group than in control group. There were no substantial difference between two groups in age, BMI, gender and medical histories. In postoperative followup, the incidence of hydronephrosis in position group was significantly lower than in control group (9.5% vs. 15.7%, p = 0.032) after removing double-J stents. In position group, the SFS of the 2nd week end (60.9% vs. 47.2%, p = 0.001), the 4th week end (74.1% vs. 62.8%, p = 0.004) and the 12th week end (86.9% vs. 79.4%, p = 0.021) were all significantly higher than those in control group. CONCLUSIONS: SHPT after holmium laser lithotripsy via FURS may increase postoperative SFS, accelerate stone fragment clearance, and decrease the incidence of hydronephrosis after removal of double-J stents. The therapy does not require professional assistance and is economical, simple, and effective.

Statistical properties of the rovibrational bound levels for Ar2Kr.

We calculate the rovibrational bound levels with total angular momentum J = 0, 1 of 40Ar284Kr trimer using the slow variable discretization method combined with the finite-element method-discrete variable representation basis. The statistical distributions of the rovibrational levels for JΠ=0e, 1e, and 1o symmetries are presented and the effects of the Axilrod-Teller potential term are considered. For the 0e and 1e symmetries, the Axilrod-Teller term makes the spectra become fully chaotic. However, for the 1o symmetry, statistical properties depend mainly on the coupling between K = 0 and K = 1 and the Axilrod-Teller term has a small effect.

Perfluorooctane sulfonate (PFOS) and benzo[a]pyrene (BaP) synergistically induce neurotoxicity in C6 rat glioma cells via the activation of neurotransmitter and Cyp1a1-mediated steroid hormone synthesis pathways.

Humans are often exposed to complex mixtures of multiple pollutants rather than a single pollutant. However, the combined toxic effects and the molecular mechanism of PFOS and BaP remain poorly understood. In this study, two typical environmental pollutants, perfluorooctane sulfonate acid (PFOS) and benzo [a]pyrene (BaP), were selected to investigate their combined neurotoxic effects on rat C6 glioma cells at environmentally relevant concentrations. The results showed that coexposure to low-dose PFOS and BaP induced greater toxicity (synergistic effect) than did single exposure. PFOS-BaP coexposure had stronger toxic effects on inducing oxidative stress and promoting early apoptosis. Targeted metabolomics confirmed that increased levels of the neurotransmitters 5-hydroxytryptophan, dopamine, tryptophan and serotonin disturb the phenylalanine, tyrosine and tryptophan biosynthesis pathways. Mechanistically, exposure to a low-dose PFOS-BaP binary mixture induces steroid hormone synthesis disorder through the activation of Cyp1a1 and Hsd17b8 (steroid hormone synthesis genes) and Dhcr24 and Dhcr7 (cholesterol synthesis genes). These findings are useful for comprehensively and systematically elucidating the biological safety of PFOS-BaP and its potential threats to human health.

Multiomics reveals new biomarkers and mechanistic insights into the combined toxicity effects of 2,2',4,4',5,5'-hexachlorobiphenyl and atrazine exposures in MCF-7 cells.

Humans are constantly exposed to complicated chemical mixtures from the environment and food rather than being exposed to a single pollutant. The underlying mechanisms of the complicated combined toxicity of endocrine disrupting chemicals (EDCs) are still mainly unexplored. In this study, two representative EDCs, 2,2',4,4',5,5'-hexachlorobiphenyl (PCB153) and atrazine (ATZ), were selected to explore their combined effects on MCF-7 cell proliferation at environmental exposure concentrations by an integrated analysis of metabolomics and transcriptomics. The results showed that 1 µM ATZ and PCB153 combined exposure significantly accelerated MCF-7 cell growth by 18.2%. More than 400 metabolites detected by UHPLC-QTOF/MS were used to observe metabolism differences induced by binary mixtures. Metabolomics analysis verified that ATZ and PCB153 exposure alone or in combination could have an additive effect on metabolism and induce significant disruption to glycolysis, purine metabolism and the TCA cycle, which provide energy demand and biosynthetic substrates for cell proliferation. Compared to PCB153 and ATZ exposure alone, a combined effect was observed in purine and pyrimidine metabolic pathways. Hexokinase 3 (HK3) and cytochrome P450 19 subfamily A1 (CYP19A1) were identified as differentially expressed genes based on transcriptomic analysis. By integrating metabolome and transcriptome analysis, the proliferation effects of ATZ and PCB153 were induced at low doses in MCF-7 cells through potential interference with the downstream transcription signaling of CYP19A1. Furthermore, molecular docking indicated that PCB153 and ATZ directly affected CYP19A1. Altogether, the regulation of pivotal metabolites and differentially expressed genes could provide helpful information to reveal the mechanism by which PCB153 and ATZ affect MCF-7 cell proliferation.

Lipoxin A4 depresses inflammation and promotes autophagy via AhR/mTOR/AKT pathway to suppress endometriosis.

BACKGROUND: Endometriosis is a benign gynecological disease with the feature of estrogen dependence and inflammation. The function of autophagy and the correlation with inflammation were not yet revealed. METHODS: Autophagosomes were detected by transmission electron microscopy. Gene Expression Omnibus (GEO) database was referred to analyze the expression of autophagy-related genes. Quantification of mRNA and protein expression was examined by qRT-PCR and Western Blot. Immunohistochemistry was performed to explore the expression of proteins in tissues. The mouse model of endometriosis was performed to analyze the autophagic activity and effect of LXA4. RESULTS: The expression of autophagy-related genes in endometriotic lesions were unusually changed. The number of autophagosomes and LC3B-II expression was diminished, and p62 was increased in ectopic lesions from both patients and mice. Interleukin 1ß (IL1ß) attenuated the expression of LC3B and promoted the level p62. The autophagy activator MG-132 upregulated the expression of LC3B and reduced IL1ß, IL6, and p62. LXA4 reversed the inhibitory effect of IL1ß on the expression of LC3B and p62, and blocking the receptor of LXA4 AhR (aryl hydrocarbon receptor) resulted in the incapacitation of LXA4 to influence the effect of IL1ß. LXA4 depressed the phosphorylation of AKT and mTOR to against IL1ß, and blocking AhR negatively regulated the effect of LXA4 on AKT/mTOR pathway. LXA4 reduced the ectopic lesions and the expression of IL1ß and p62, but enhanced LC3B-II in endometriotic mouse models. CONCLUSION: In endometriosis, increased inflammation of ectopic lesions prominently depresses autophagy. LXA4 could regulate autophagy by suppressing inflammatory response through AhR/AKT/mTOR pathway.

Rice miR1432 Fine-Tunes the Balance of Yield and Blast Disease Resistance via Different Modules.

microRNAs act as fine-tuners in the regulation of plant growth and resistance against biotic and abiotic stress. Here we demonstrate that rice miR1432 fine-tunes yield and blast disease resistance via different modules. Overexpression of miR1432 leads to compromised resistance and decreased yield, whereas blocking miR1432 using a target mimic of miR1432 results in enhanced resistance and yield. miR1432 suppresses the expression of LOC_Os03g59790, which encodes an EF-hand family protein 1 (OsEFH1). Overexpression of OsEFH1 leads to enhanced rice resistance but decreased grain yield. Further study revealed that miR1432 and OsEFH1 are differentially responsive to chitin, a fungus-derived pathogen/microbe-associated molecular pattern (PAMP/MAMP). Consistently, blocking miR1432 or overexpression of OsEFH1 improves chitin-triggered immunity responses. In contrast, overexpression of ACOT, another target gene regulating rice yield traits, has no significant effects on rice blast disease resistance. Altogether, these results indicate that miR1432 balances yield and resistance via different target genes, and blocking miR1432 can simultaneously improve yield and resistance.

Blocking miR530 Improves Rice Resistance, Yield, and Maturity.

MicroRNAs fine-tune plant growth and resistance against multiple biotic and abiotic stresses. The trade-off between biomass and resistance can penalize crop yield. In this study, we have shown that rice miR530 regulates blast disease resistance, yield, and growth period. While the overexpression of miR530 results in compromised blast disease resistance, reduced grain yield, and late maturity, blocking miR530 using a target mimic (MIM530) leads to enhanced resistance, increased grain yield, and early maturity. Further study revealed that the accumulation of miR530 was decreased in both leaves and panicles along with the increase of age. Such expression patterns were accordant with the enhanced resistance from seedlings to adult plants, and the grain development from panicle formation to fully-filled seeds. Divergence analysis of miR530 precursor with upstream 1,000-bp promoter sequence in 11 rice species revealed that miR530 was diverse in Oryza sativa japonica and O. sativa indica group, which was consistent with the different accumulation of miR530 in japonica accessions and indica accessions. Altogether, our results indicate that miR530 coordinates rice resistance, yield, and maturity, thus providing a potential regulatory module for breeding programs aiming to improve yield and disease resistance.

[Stoichiometric Characteristics of Purple Sloping Cropland Under Long-term Fertilization and Cultivation].

Clarification of the effects of long-term fertilization and cultivation on soil organic carbon (C), nitrogen (N), phosphorus (P), and potassium (K) contents and their stoichiometric ratios can contribute to existing research on the C and nutrient biogeochemical cycles and their interacting mechanisms. Such information is also of great significance to fertilization management and for the control of non-point pollution. Fifteen plots (8 m long, 4 m wide) were set up on a representative purple hillslope (15°). Five treatments (three replications) were used on the plots:i) no fertilizer with downslope cultivation (CK), ii) combined application of manure and fertilizer with downslope cultivation (T1), iii) chemical fertilizers with downslope cultivation (T2), iv) chemical fertilizer with increasing fertilization with downslope cultivation (T3), and v) chemical fertilizer with contour cultivation (T4). The C, N, P and K contents and their ratios in the five treatments corresponding to 0-10 cm and 10-20 cm soil depths were compared. The results showed that C, N and P contents for the different treatments were differed significant and could be ranked:T1 > T3 > T4 > T2 > CK (P<0.05). K content was not significantly different among the four fertilizations (P>0.05) but was significantly higher than the CK treatment (P<0.05), and could be ranked:T4 > T3 > T2 > T1 > CK. The C:N ratios in the five treatments were significantly different (P<0.05) at a soil depth of 10-20 cm (T4 > T3 > T1 > CK > T2). The C:P ratios in the five treatments were significantly different (P<0.05) at a soil depth of 0-10 cm (T1 > T3 > CK > T4 > T2). The C:K, N:P, N:K, and P:K ratios for the five treatments at both of the soil depths showed significant differences (P<0.05), and the C:K, N:K, and P:K were ranked as T1 > T3 > T4 > T2 > CK, whereas the N:P ratio was ranked as T1 > CK > T4 > T3 > T2. The C, N, P, and K contents and their stoichiometric ratios decreased with increasing soil depth. Soil C, N and P in the study site showed moderate variations based on their coefficient of variation (CV):37.50%, 38.91%, and 25.35%, respectively. Soil K on the other hand showed a weak variation (CV 5.03%). Soil C:N and C:P also showed a weak variation with a CV of 7.52% and 14.38%, respectively. Soil C:K, N:P, N:K, and P:K showed moderate variations, with a CV of 35.62%, 17.01%, 37.24% and 44.78%, respectively. There were significant positive interrelations among soil C, N, P, and K contents and their stoichiometric ratios (P<0.05). The average N:P ratio was 2.09, which was much lower than the average value for various soil types in China. Our results indicate that soil N is the key limiting nutrient in purple hillslope land, and that the combination of organic and inorganic fertilizers can effectively alleviate the N deficiency in the study area.

Inhibitory mechanism and molecular analysis of furoic acid and oxalic acid on lipase.

Lipase hydrolyzes fat to free fatty acid and monoacylglycerol, which can be absorbed. Lipase inhibitors reduce the absorption of fat by intestinal cells. In this paper, we explored a novel treatment for obesity. Lipase was strongly inhibited by furoic acid and oxalic acid (IC50 of 2.12 ±â€¯0.04 and 15.05 ±â€¯0.78 mM, respectively). The inhibition by furoic acid was non-competitive, while that of oxalic acid was competitive (inhibition constant 2.12 ±â€¯0.04 and 10.6 ±â€¯0.17 mM, respectively). Quenching was static. With increasing concentration of inhibitor, the peaks of enzyme fluorescence declined. Docking results suggested that furoic acid and oxalic acid could interact with the amino acid residues of the active center of lipase.