Combinatorial design is an effective strategy to acquire the optimal solution in complex systems. In this study, the combined effects of pathway combination, promoters' strength fine-tuning, copy ...numbers and integration locus variations caused by δ-integration were explored in Saccharomyces cerevisiae using geranylgeraniol (GGOH) production as an example. Two GGOH biosynthetic pathway branches were constructed. In branch 1, GGOH was converted from isopentenyl pyrophosphate (IPP) and farnesyl diphosphate (FPP). In branch 2, GGOH was derived directly from IPP and dimethylallyl pyrophosphate (DMAPP). Regulated by 10 combinations of 11 diverse promoters, a fusion gene BTS1-ERG20, a heterologous geranylgeranyl diphosphate synthase from Sulfolobus acidocaldarius (GGPPSsa) and an endogenous N-terminal truncated gene 3-hydroxyl-3-methylglutaryl-CoA reductase isoenzyme 1 (tHMGR), were incorporated into yeast by δ-integration, leading to a series of GGOH producing strains with yields ranging from 18.45 mg/L to 161.82 mg/L. The yield was further increased to 437.52 mg/L by optimizing the fermentation medium. Consequently, the GGOH yield reached 1315.44 mg/L in a 5-L fermenter under carbon restriction strategy. Our study not only opens large opportunities for downstream diterpenes overproductions, but also demonstrates that pathway optimization based on combinatorial design is a promising strategy to engineer microbes for overproducing natural products with complex structure.
Amplitude of low‐frequency fluctuation (ALFF) has been widely used for localization of abnormal activity at the single‐voxel level in resting‐state fMRI (RS‐fMRI) studies. However, previous ALFF ...studies were based on fast Fourier transform (FFT‐ALFF). Our recent study found that ALFF based on wavelet transform (Wavelet‐ALFF) showed better sensitivity and reproducibility than FFT‐ALFF. The current study aimed to test the reliability and validity of Wavelet‐ALFF, and apply Wavelet‐ALFF to investigate the modulation effect of repetitive transcranial magnetic stimulation (rTMS). The reliability and validity were assessed on multicenter RS‐fMRI datasets under eyes closed (EC) and eyes open (EO) conditions (248 healthy participants in total). We then detected the sensitivity of Wavelet‐ALFF using a rTMS modulation dataset (24 healthy participants). For each dataset, Wavelet‐ALFF based on five mother wavelets (i.e., db2, bior4.4, morl, meyr and sym3) and FFT‐ALFF were calculated in the conventional band and five frequency sub‐bands. The results showed that the reliability of both inter‐scanner and intra‐scanner was higher with Wavelet‐ALFF than with FFT‐ALFF across multiple frequency bands, especially db2‐ALFF in the higher frequency band slow‐2 (0.1992–0.25 Hz). In terms of validity, the multicenter ECEO datasets showed that the effect sizes of Wavelet‐ALFF with all mother wavelets (especially for db2‐ALFF) were larger than those of FFT‐ALFF across multiple frequency bands. Furthermore, Wavelet‐ALFF detected a larger modulation effect than FFT‐ALFF. Collectively, Wavelet db2‐ALFF showed the best reliability and validity, suggesting that db2‐ALFF may offer a powerful metric for inspecting regional spontaneous brain activities in future studies.
Using multicenter RS‐fMRI datasets under EC and EO conditions and a single‐session rTMS modulation dataset, this study provides evidence of the superiority of Wavelet‐ALFF (especially db2‐ALFF) over FFT‐ALFF in improving reliability and validity and increasing statistical significance. Therefore, db2‐ALFF may offer a powerful metric for inspecting regional spontaneous brain activities in future studies.
Introduction The prevalence of obesity in Chinese adults increased from 1991 to 2000; however, recent changes in this trend are unclear. This study aims to estimate the current prevalence of obesity ...and to assess trends in obesity and BMI distribution in Chinese adults from 1991 through 2011. Methods Height and weight measurements of 12,249 Chinese adults from the 2011 China Health and Nutrition Survey were analyzed (in 2013) together with China Health and Nutrition Survey data for 1991−2009. Obesity was defined as BMI≥28.0 kg/m2 based on the Working Group on Obesity in China criteria. Results In the 2011 survey, the age-adjusted mean BMI was 23.8 (95% CI=23.7, 23.9) for men and 23.4 (95% CI=23.2, 23.5) for women. The age-adjusted prevalence of obesity was 11.3% (95% CI=10.8%, 11.9%) overall, 11.8% (95% CI=10.8%, 12.6%) among men, and 11.0% (95% CI=10.3%, 11.8%) among women. Estimates of age-adjusted obesity prevalence among the Chinese population were significantly lower than those of the U.S. population (all p <0.05). Over the 20-year period, the prevalence of obesity increased from 2.88% to 11.8% among men (age-adjusted annual change in OR=1.08, 95% CI=1.07, 1.09, p <0.001) and from 4.55% to 11.0% among women (OR=1.05, 95% CI=1.05, 1.06, p <0.001). Similar significant findings were observed for both men and women based on WHO recommendations. Conclusions The prevalence of obesity among both Chinese men and women increased significantly from 1991 through 2011, particularly among men.
Summary
Soybean (Glycine max) is an important crop for oil and protein resources worldwide. The molecular mechanism of the abiotic stress response in soybean is largely unclear. We previously ...identified multiple stress‐responsive WRKY genes from soybean. Here, we further characterized the roles of one of these genes, GmWRKY27, in abiotic stress tolerance using a transgenic hairy root assay. GmWRKY27 expression was increased by various abiotic stresses. Over‐expression and RNAi analysis demonstrated that GmWRKY27 improves salt and drought tolerance in transgenic soybean hairy roots. Measurement of physiological parameters, including reactive oxygen species and proline contents, supported this conclusion. GmWRKY27 inhibits expression of a downstream gene GmNAC29 by binding to the W–boxes in its promoter region. The GmNAC29 is a negative factor of stress tolerance as indicated by the performance of transgenic hairy roots under stress. GmWRKY27 interacts with GmMYB174, which also suppresses GmNAC29 expression and enhances drought stress tolerance. The GmWRKY27 and GmMYB174 may have evolved to bind to neighbouring cis elements in the GmNAC29 promoter to co‐reduce promoter activity and gene expression. Our study discloses a valuable mechanism in soybean for regulation of the stress response by two associated transcription factors. Manipulation of these genes should facilitate improvements in stress tolerance in soybean and other crops.
Significance Statement
Our results suggest that GmWRKY27 play a critical role in abiotic stress response and provide a valuable perspective of how transcription factors work to confer stress tolerance.
ObjectiveProgranulin (PGRN) was previously isolated as an osteoarthritis (OA)-associated growth factor. Additionally, PGRN was found to play a therapeutic role in inflammatory arthritis mice models ...through antagonising tumour necrosis factor α (TNF-α). This study was aimed at investigating the role of PGRN in degradation of cartilage and progression of OA.MethodsProgression of OA was analysed in both spontaneous and surgically induced OA models in wild type and PGRN-deficient mice. Cartilage degradation and OA were evaluated using Safranin O staining, immunohistochemistry and ELISA. Additionally, mRNA expression of degenerative factors and catabolic markers known to be involved in cartilage degeneration in OA were analysed. Furthermore, the anabolic effects and underlying mechanisms of PGRN were investigated by in vitro experiments with primary chondrocytes.ResultsHere, we found that deficiency of PGRN led to spontaneous OA-like phenotype in ‘aged’ mice. Additionally, PGRN-deficient mice exhibited exaggerated breakdown of cartilage structure and OA progression, while local delivery of recombinant PGRN protein attenuated degradation of cartilage matrix and protected against OA development in surgically induced OA models. Furthermore, PGRN activated extracellular signal-regulated kinases (ERK) 1/2 signalling and elevated the levels of anabolic biomarkers in human chondrocyte, and the protective function of PGRN was mediated mainly through TNF receptor 2. Additionally, PGRN suppressed inflammatory action of TNF-α and inhibited the activation of β-Catenin signalling in cartilage and chondrocytes.ConclusionsCollectively, this study provides new insight into the pathogenesis of OA, and also presents PGRN as a potential target for the treatment of joint degenerative diseases, including OA.
Direct manipulation of readily accessible trifluoromethyl alkenes (TAs) represents an attractive approach to the preparation of diversified fluorine‐containing compounds. In this study, ...defluorinative alkylation reactions of TAs with a broad array of soft carbon nucleophiles have been documented. Nucleophilic substitutions occur enabled by a catalytic amount of base, providing access to tertiary alkyl substituted gem‐difluoroalkenes and 2‐fluoro‐4H‐pyrans. By extending the nucleophiles to silyl enol ethers, defluorination can be achieved in the absence of base to give gem‐difluoroalkenes. This process, which eliminates the requirement of organometallic reagents, transition metals, or strong bases for the C−F bond cleavage, is applicable to late‐stage modification of complex molecules.
Although the substitution of Cu by Ag to suppress CuZn defects offers several advantages in overcoming the large open-circuit voltage (Voc) deficit for Cu2ZnSn(S,Se)4 (CZTSSe) solar cells, an ...excellent performance has not been achieved to date primarily due to the Fermi level pinning at the CdS/absorber interface and large recombination at the absorber/Mo interface. Herein, we developed a composition grading strategy to achieve a V-shaped Ag-graded structure with a higher Ag content on both the back and front surfaces of the (Cu,Ag)2ZnSn(S,Se)4 (CAZTSSe) layer. The key advantages of this Ag-graded structure are as follows: the higher content towards the CdS/absorber interface can create weak n-type donor defects and retard Fermi level pinning, whereas the lower content at the interlayer maintains the conductivity and light absorption; moreover, the other higher content towards Mo back contact can effectively suppress the recombination and improve the utilization of long-wave incident light. By appropriately adjusting the Ag gradient, we demonstrated a significant increase in Voc, and an unexpected conversion efficiency of 11.2% was achieved. This is the highest efficiency achieved to date for Ag-substituted CZTSSe solar cells, and the result supports a new aspect that synthesis of a composition-graded CAZTSSe absorber has great potential for future research.
As the effects of global warming on climate have a wide spatial variability, regional studies of temporal climate trends are critical. This study investigates the effect of global warming on ...temperature and precipitation trends in the Yellow, Yangtze and Pearl River basins (the Three Basins) of China over the past 58 years (1956–2013). Over this time period, the mean warming rate in the Three Basins (0.22 °C/10 yr) was close to that for the global land surface (0.21 °C/10 yr). However, the warming rate showed high spatial variability across the study region, ranging from 0.05 °C/10 yr to 0.49 °C/10 yr. These rates tend to increase with latitude and elevation and toward very large cities (e.g., Shanghai). The warming rate in the Three Basins varied by season, it was lower in summer (0.14 °C/10 yr) and higher in winter (0.29 °C/10 yr). In spite of the warming trend, no statistically significant increase or decrease in precipitation was found for the Three Basins over the past 58 years.
Currently, glycated hemoglobin A1c (HbA1c) has been widely used to assess the glycemic control of patients with diabetes. However, HbA1c has certain limitations in describing both short-term and ...long-term glycemic control. To more accurately evaluate the glycemic control of diabetes patients, the continuous glucose monitoring (CGM) technology has emerged. CGM technology can provide robust data on short-term glycemic control and introduce new monitoring parameters such as time in range, time above range, and time below range as indicators of glycemic fluctuation. These indicators are used to describe the changes in glycemic control after interventions in clinical research or treatment modifications in diabetes patient care. Recent studies both domestically and internationally have shown that these indicators are not only associated with microvascular complications of diabetes mellitus but also closely related to cardiovascular disease complications and prognosis. Therefore, this article aims to comprehensively review the association between CGM-based glycemic parameters and cardiovascular disease complications by analyzing a large number of domestic and international literature. The purpose is to provide scientific evidence and guidance for the standardized application of these indicators in clinical practice, in order to better evaluate the glycemic control of diabetes patients and prevent the occurrence of cardiovascular disease complications. This research will contribute to improving the quality of life for diabetes patients and provide important references for clinical decision-making.
Poly(ADP-ribose) polymerase 1 (PARP1) regulates gene transcription in addition to functioning as a DNA repair factor. Forkhead box O1 (FoxO1) is a transcription factor involved in extensive ...biological processes. Here, we report that PARP1 binds to two separate motifs on the FoxO1 promoter and represses its transcription in a polymerase-independent manner. Using PARP1-knock out (KO) cells, wild-type-PARP1-complemented cells and catalytic mutant PARP1
-reconstituted cells, we investigated transcriptional regulation by PARP1. PARP1 loss led to reduced DNA damage response and ~362-fold resistance to five PARP inhibitors (PARPis) in Ewing sarcoma cells. RNA sequencing showed 492 differentially expressed genes in a PARP1-KO subline, in which the FoxO1 mRNA levels increased up to more than five times. The change in the FoxO1 expression was confirmed at both mRNA and protein levels in different PARP1-KO and complemented cells. Moreover, exogenous PARP1 overexpression reduced the endogenous FoxO1 protein in RD-ES cells. Competitive EMSA and ChIP assays revealed that PARP1 specifically bound to the FoxO1 promoter. DNase I footprinting, mutation analyses, and DNA pulldown FREP assays showed that PARP1 bound to two particular nucleotide sequences separately located at -813 to -826 bp and -1805 to -1828 bp regions on the FoxO1 promoter. Either the PARPi olaparib or the PARP1 catalytic mutation (E988K) did not impair the repression of PARP1 on the FoxO1 expression. Exogenous FoxO1 overexpression did not impair cellular PARPi sensitivity. These findings demonstrate a new PARP1-gene promoter binding mode and a new transcriptional FoxO1 gene repressor.
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