Meta-analysis addressing the potential of antibiotic resistance gene elimination through aerobic composting.

The significant increase in antibiotic resistance genes (ARGs) in organic solid wastes (OSWs) has emerged as a major threat to the food chain. Aerobic composting is a widely used technology for OSW management, with the potential to influence the fate of AGRs. However, the variability of the ARG elimination effects reported in different studies has highlighted the uncertainty regarding the effects of composting on ARGs. To identify the potential of composting in reducing ARG and the factors (e.g., composting technologies and physiochemical properties) influence ARG changes, a meta-analysis was conducted with a database including 4,232 observations. The abundances of ARGs and mobile genetic elements (MGEs) can be substantially reduced by 74.3% and 78.8%, respectively, via aerobic composting. During composting, the ARG levels in chicken and swine manure tended to be reduced more significantly (81.7% and 78.0%) compared to those in cattle manure (52.3%) and sewage sludge (32.6%). The reduction rate of sulfonamide resistant genes was only 35.3%, which was much lower than those of other types. MGEs and composting duration (CD) were identified as the most important factors driving ARG changes during composting. These findings provide a comprehensive insight into the effects of composting on ARG reduction, which may help prevent the transmission in food systems.

Deciphering the binding behavior and interaction mechanism of apigenin and α-glucosidase based on multi-spectroscopic and molecular simulation studies.

This study investigated the molecular mechanism underlying the binding interaction between apigenin (API) and α-glucosidase (α-glu) by a combination of experimental techniques and computational simulation strategies. The spontaneously formation of stable API-α-glu complex was mainly driven by hydrogen bonds and hydrophobic forces, leading to a static fluorescence quenching of α-glu. The binding of API induced secondary structure and conformation changes of α-glu, decreasing the surface hydrophobicity of protein. Computational simulation results demonstrated that API could bind into the active cavity of α-glu via its interaction with active residues at the binding site. The important roles of key residues responsible for the binding stability and affinity between API and α-glu were further revealed by MM/PBSA results. In addition, it can be found that the entrance of active site tended to close after API binding as a result of its interaction with gate keeping residues. Furthermore, the structural basis for the binding interaction behavior of API was revealed and visualized by weak interaction analysis. The findings of our study revealed atomic-level mechanism of the interaction between API, which might shed light on the development of better inhibitors.

Precision co-composting of multi-source organic solid wastes provide a sustainable waste management strategy with high eco-efficiency: a life cycle assessment.

With the increase of organic solid wastes (OSWs), current waste management practices, such as landfill, incineration, and windrow composting, have shown weaknesses in both resource recycling and environmental protection. Co-composting has been used to achieve nutrient and carbon recycling but is accused of high ammonia emission and low degradation efficiency. Therefore, this study developed a precision co-composting strategy (S3, which adds functional bacteria generated from food processing waste to a co-composting system) and compared it with the current OSW treatment strategy (S1) and traditional co-composting strategy (S2) from a life cycle assessment (LCA) perspective. The results showed that compared with S1, the eco-efficiency increased by 31.3% due to the higher economic profit of S2 but did not directly reduce the environmental cost. The addition of bacterial agents reduced ammonia emissions and shortened composting time, so compared with S1 and S2, the environmental cost of S3 was reduced by 37.9 and 43.6%, while the economic profit increased by 79.8 and 24.4%, respectively. The changes in environmental costs and economic benefits resulted in a huge improvement of S3's eco-efficiency, which was 189.6 and 121.7% higher than S1 and S2. Meanwhile, the adoption of S3 at a national scale in China could reduce the emission of 1,4-dichlorobenzene by 99.9% compared with S1 and increase profits by 6.58 billion USD per year. This study proposes a novel approach that exhibits high eco-efficiency in the treatment of OSWs.

Chaenomeles sinensis (Thouin) Koehne fruit polyphenols alleviate high-fat diet-induced obesity and liver steatosis by improving lipid metabolism in mice.

Chaenomeles sinensis (Thouin) Koehne fruit is a rich source of medicinally and nutritionally important natural phytochemicals that benefit human health. Based on the information provided, we hypothesized that Chaenomeles sinensis (Thouin) Koehne fruit polyphenols (CSFP) possessed in vivo protective effect of on high-fat diet (HFD)-induced obesity and hepatic steatosis. Specific pathogen-free male C57BL/6J mice were randomly divided into 3 groups and fed with a low-fat diet, HFD, or HFD supplemented with CSFP by intragastric administration for 14 weeks. Obesity-related biochemical indexes and hepatic gene expression profile were determined. The findings of this study demonstrated notable reductions in body weight gain, serum triglycerides, total cholesterol, low-density lipoprotein cholesterol, and steatosis grade in the group supplemented with CSFP compared with the HFD group. Gene expression analysis provided insights into the molecular mechanisms, demonstrating that CSFP downregulated the expression of key genes involved in lipogenesis (e.g., Fas, Fads2, Scd1) and upregulated the genes associated with fatty acid oxidation (e.g., Pparα, Cpt1a, Acox1), while also suppressing genes implicated in cholesterol homeostasis (e.g., HMGCoR, Insig1, AdipoR2). These molecular changes suggest that CSFP exerts protective effects by modulating hepatic lipid metabolism pathways, thereby mitigating the metabolic derangements associated with HFD-induced obesity and hepatic steatosis.

Mechanisms of mitigating nitrous oxide emission during composting by biochar and calcium carbonate addition.

To investigate the mechanisms underlying effects of biochar and calcium carbonate (CaCO3) addition on nitrous oxide (N2O) emissions during composting, this paper conducted a systematic study on mineral nitrogen (N), dissolved organic carbon (C) and N, sources of N2O, and functional genes. Biochar and CaCO3 addition decreased N2O emissions by 26.5-47.8% (9.5-96.9 mg N kg-1 dw) and 13.9-37.4% (12.0-121.0 mg N kg-1 dw) compared to the control (14.3-179.7 mg N kg-1 dw), respectively. The mitigation of N2O emission was caused by decreased contribution of ammonia-oxidizing bacteria (AOB) and fungi to N2O production due to diminished AOB amoA, fungal nirK and P450 gene abundances, or by stimulated N2O reduction to N2 owing to increased abundances of nosZⅠ and nosZⅠⅠ genes under biochar and CaCO3 addition. The findings suggest that the addition of biochar or CaCO3 is effective in mitigating N2O emission during composting.

Unraveling allostery within the angiotensin II type 1 receptor for Gαq and ß-arrestin coupling.

G protein-coupled receptors engage both G proteins and ß-arrestins, and their coupling can be biased by ligands and mutations. Here, to resolve structural elements and mechanisms underlying effector coupling to the angiotensin II (AngII) type 1 receptor (AT1R), we combined alanine scanning mutagenesis of the entire sequence of the receptor with pharmacological profiling of Gαq and ß-arrestin engagement to mutant receptors and molecular dynamics simulations. We showed that Gαq coupling to AT1R involved a large number of residues spread across the receptor, whereas fewer structural regions of the receptor contributed to ß-arrestin coupling regulation. Residue stretches in transmembrane domain 4 conferred ß-arrestin bias and represented an important structural element in AT1R for functional selectivity. Furthermore, we identified allosteric small-molecule binding sites that were enclosed by communities of residues that produced biased signaling when mutated. Last, we showed that allosteric communication within AT1R emanating from the Gαq coupling site spread beyond the orthosteric AngII-binding site and across different regions of the receptor, including currently unresolved structural regions. Our findings reveal structural elements and mechanisms within AT1R that bias Gαq and ß-arrestin coupling and that could be harnessed to design biased receptors for research purposes and to develop allosteric modulators.

Molecular insights into intrinsic transducer-coupling bias in the CXCR4-CXCR7 system.

Chemokine receptors constitute an important subfamily of G protein-coupled receptors (GPCRs), and they are critically involved in a broad range of immune response mechanisms. Ligand promiscuity among these receptors makes them an interesting target to explore multiple aspects of biased agonism. Here, we comprehensively characterize two chemokine receptors namely, CXCR4 and CXCR7, in terms of their transducer-coupling and downstream signaling upon their stimulation by a common chemokine agonist, CXCL12, and a small molecule agonist, VUF11207. We observe that CXCR7 lacks G-protein-coupling while maintaining robust ßarr recruitment with a major contribution of GRK5/6. On the other hand, CXCR4 displays robust G-protein activation as expected but exhibits significantly reduced ßarr-coupling compared to CXCR7. These two receptors induce distinct ßarr conformations even when activated by the same agonist, and CXCR7, unlike CXCR4, fails to activate ERK1/2 MAP kinase. We also identify a key contribution of a single phosphorylation site in CXCR7 for ßarr recruitment and endosomal localization. Our study provides molecular insights into intrinsic-bias encoded in the CXCR4-CXCR7 system with broad implications for drug discovery.

The Retrieval and Effect of Core Parameters for Near-Field Inter-Body Coupling Communication.

The potential of the Internet of Body (IoB) to support healthcare systems in the future lies in its ability to enable proactive wellness screening through the early detection and prevention of diseases. One promising technology for facilitating IoB applications is near-field inter-body coupling communication (NF-IBCC), which features lower power consumption and higher data security when compared to conventional radio frequency (RF) communication. However, designing efficient transceivers requires a profound understanding of the channel characteristics of NF-IBCC, which remain unclear due to significant differences in the magnitude and passband characteristics of existing research. In response to this problem, this paper clarifies the physical mechanisms of the differences in the magnitude and passband characteristics of NF-IBCC channel characteristics in existing research work through the core parameters that determine the gain of the NF-IBCC system. The core parameters of NF-IBCC are extracted through the combination of transfer functions, finite element simulations, and physical experiments. The core parameters include the inter-body coupling capacitance (CH), the load impedance (ZL), and the capacitance (Cair), coupled by two floating transceiver grounds. The results illustrate that CH, and particularly Cair, primarily determine the gain magnitude. Moreover, ZL mainly determines the passband characteristics of the NF-IBCC system gain. Based on these findings, we propose a simplified equivalent circuit model containing only core parameters, which can accurately capture the gain characteristics of the NF-IBCC system and help to concisely describe the channel characteristics of the system. This work lays a theoretical foundation for developing efficient and reliable NF-IBCC systems that can support IoB for early disease detection and prevention in healthcare applications. The potential benefits of IoB and NF-IBCC technology can, thus, be fully realized by developing optimized transceiver designs based on a comprehensive understanding of the channel characteristics.

KMT2D links TGF-ß signaling to noncanonical activin pathway and regulates pancreatic cancer cell plasticity.

Although KMT2D, also known as MLL2, is known to play an essential role in development, differentiation, and tumor suppression, its role in pancreatic cancer development is not well understood. Here, we discovered a novel signaling axis mediated by KMT2D, which links TGF-ß to the activin A pathway. We found that TGF-ß upregulates a microRNA, miR-147b, which in turn leads to post-transcriptional silencing of KMT2D. Loss of KMT2D induces the expression and secretion of activin A, which activates a noncanonical p38 MAPK-mediated pathway to modulate cancer cell plasticity, promote a mesenchymal phenotype, and enhance tumor invasion and metastasis in mice. We observed a decreased KMT2D expression in human primary and metastatic pancreatic cancer. Furthermore, inhibition or knockdown of activin A reversed the protumoral role of KMT2D loss. These findings support a tumor-suppressive role of KMT2D in pancreatic cancer and identify miR-147b and activin A as novel therapeutic targets.

Quantification of N and C cycling during aerobic composting, including automated direct measurement of N2, N2O, NO, NH3, CO2 and CH4 emissions.

Closing the carbon (C) and nitrogen (N) balance has yet to be achieved in aerobic bioprocess due to current methodological drawbacks in the frequency of sampling and detection and the challenge in direct measurement of instantaneous N2 emission. To address this issue, a novel system was developed enabling simultaneous and online determination of gaseous C and N species (N2, N2O, NO, NH3, CO2 and CH4) from aerobic composting at a high frequency of 120 times·d-1. A helium­oxygen gas mixture was used to replace the air in the system to enable direct measurement of N2 emission, and three different gas exchange methods were assessed in their ability to minimize atmospheric background N2: 1) the N2-free gas purging method; 2) one cycle of the evacuation-refilling procedure; 3) one cycle of evacuating and refilling followed by N2-free gas purging. Method 3 was demonstrated as an optimum N2-removal method, and background N2 concentrations decreased to ~66 µmol·mol-1 within 11.6 h. During the N2-free gas purging period, low temperature incubation at 15 °C reduced CO2, CH4, NO, N2O and NH3 losses by 80.5 %, 41-fold, 10-fold, 11,403-fold and 61.4 %, respectively, compared with incubation at 30 °C. Therefore, a fast and low-perturbation N2 removal method was developed, namely the evacuating/refilling-low temperature purging method. Notably, all C and N gases exhibited large within-day variations during the peak emission period, which can be addressed by high-frequency measurement. Based on the developed method, up to 97.8 % of gaseous C and 95.6 % of gaseous N losses were quantified over a 43-day compost incubation, with N2 emission accounting (on average) for 5.8 % of the initial total N. This system for high frequency measurement of multiple gases (including N2) provides a novel tool for obtaining a deeper understanding of C and N turnover and more accurate estimation of reactive N and greenhouse gas emissions during composting.

Prostaglandin F2α and angiotensin II type 1 receptors exhibit differential cognate G protein coupling regulation.

Promiscuous G protein-coupled receptors (GPCRs) engage multiple Gα subtypes with different efficacies to propagate signals in cells. A mechanistic understanding of Gα selectivity by GPCRs is critical for therapeutic design, since signaling can be restrained by ligand-receptor complexes to preferentially engage specific G proteins. However, details of GPCR selectivity are unresolved. Here, we investigated cognate G protein selectivity using the prototypical promiscuous Gαq/11 and Gα12/13 coupling receptors, angiotensin II type I receptor (AT1R) and prostaglandin F2α receptor (FP), bioluminescence resonance energy transfer-based G protein and pathway-selective sensors, and G protein knockout cells. We determined that competition between G proteins for receptor binding occurred in a receptor- and G protein-specific manner for AT1R and FP but not for other receptors tested. In addition, we show that while Gα12/13 competes with Gαq/11 for AT1R coupling, the opposite occurs for FP, and Gαq-mediated signaling regulated G protein coupling only at AT1R. In cells, the functional modulation of biased ligands at FP and AT1R was contingent upon cognate Gα availability. The efficacy of AT1R-biased ligands, which poorly signal through Gαq/11, increased in the absence of Gα12/13. Finally, we show that a positive allosteric modulator of Gαq/11 signaling that also allosterically decreases FP-Gα12/13 coupling, lost its negative modulation in the absence of Gαq/11 coupling to FP. Together, our findings suggest that despite preferential binding of similar subsets of G proteins, GPCRs follow distinct selectivity rules, which may contribute to the regulation of ligand-mediated G protein bias of AT1R and FP.

The effects of electric field assisted composting on ammonia and nitrous oxide emissions varied with different electrolytes.

Enhancing electron transfer through directly elevating electric potential has been verified to reduce gaseous emissions from composting. Reducing electric resistance of composting biomass might be a choice to further strengthening electron transfer. Here, the effects of chemical electrolytes addition on gaseous Nitrogen emission in electric field assistant composting were investigated. Results suggest that adding acidic electrolyte (ferric chloride) significantly reduced ammonia (NH3) emission by 72.1% but increased nitrous oxide (N2O) emission (by 24-fold) (P < 0.05), because of a dual effect on nitrifier activity: i) an elevated abundance and proportion of ammonia oxidizing bacteria Nitrosomonadaceae, and ii) delayed growth of nitrite oxidizing bacteria. Neutral and alkaline electrolytes had no negative or positive effect on N2O or NH3 emission. Hence, there is a potential trade-off between NH3 and N2O mitigation if using ferric chloride as acidic electrolyte, and electrolyte addition should aim to enhance electron production promote N2O mitigation.

Camouflaged Instance Segmentation In-the-Wild: Dataset, Method, and Benchmark Suite.

This paper pushes the envelope on decomposing camouflaged regions in an image into meaningful components, namely, camouflaged instances. To promote the new task of camouflaged instance segmentation of in-the-wild images, we introduce a dataset, dubbed CAMO++, that extends our preliminary CAMO dataset (camouflaged object segmentation) in terms of quantity and diversity. The new dataset substantially increases the number of images with hierarchical pixel-wise ground truths. We also provide a benchmark suite for the task of camouflaged instance segmentation. In particular, we present an extensive evaluation of state-of-the-art instance segmentation methods on our newly constructed CAMO++ dataset in various scenarios. We also present a camouflage fusion learning (CFL) framework for camouflaged instance segmentation to further improve the performance of state-of-the-art methods. The dataset, model, evaluation suite, and benchmark will be made publicly available on our project page.

Intrinsic bias at non-canonical, ß-arrestin-coupled seven transmembrane receptors.

G-protein-coupled receptors (GPCRs), also known as seven transmembrane receptors (7TMRs), typically interact with two distinct signal-transducers, i.e., G proteins and ß-arrestins (ßarrs). Interestingly, there are some non-canonical 7TMRs that lack G protein coupling but interact with ßarrs, although an understanding of their transducer coupling preference, downstream signaling, and structural mechanism remains elusive. Here, we characterize two such non-canonical 7TMRs, namely, the decoy D6 receptor (D6R) and the complement C5a receptor subtype 2 (C5aR2), in parallel with their canonical GPCR counterparts. We discover that D6R and C5aR2 efficiently couple to ßarrs, exhibit distinct engagement of GPCR kinases (GRKs), and activate non-canonical downstream signaling pathways. We also observe that ßarrs adopt distinct conformations for D6R and C5aR2, compared to their canonical GPCR counterparts, in response to common natural agonists. Our study establishes D6R and C5aR2 as ßarr-coupled 7TMRs and provides key insights into their regulation and signaling with direct implication for biased agonism.

Nitrifier denitrification dominates nitrous oxide production in composting and can be inhibited by a bioelectrochemical nitrification inhibitor.

Targeted options to reduce nitrous oxide (N2O) emission from composting is scarce due to challenges in disentangling the complex N2O production pathways. Here, combined approaches of nitrogen form analysis, isotopocule mapping, quantitative PCR, and Illumina MiSeq sequencing were used to differentiate N2O production pathways and decipher the underlying biochemical mechanisms. Results suggested that most N2O was produced at the latter stage through nitrifier denitrification. The bioelectrochemical assistance through applying an electric potential reduced N2O emissions by 28.5-75.5%, and the underlying mitigation mechanism was ammonia oxidation repression, as evidenced by the observed reduction in the proportion of the amoA containing family Nitrosomonadaceae from 99% to 83% at the lower voltage and to a negligible level at the higher voltage assessed, which was attributed to their depressed competitiveness for oxygen with heterotrophs. The findings provide evidence that the bioelectrochemical assistance could function as a nitrification inhibitor to minimize compost derived N2O emissions.

Rates and trends in stage-specific prostate cancer incidence by age and race/ethnicity, 2000-2017.

BACKGROUND: The 2008 and 2012 United States Preventive Services Task Force (USPSTF) recommendations against prostate-specific antigen (PSA) screening have led to changes in the incidence pattern of prostate cancer. We sought to examine rates and trends in stage-specific prostate cancer incidence by age and race/ethnicity using the most recent data obtained from Surveillance, Epidemiology, and End Results (SEER) program. METHODS: SEER*Stat version 8.3.6 was used to analyze annual prostate cancer incidence rates between 2000 and 2017 according to the SEER summary stage, age group, and race/ethnicity group. Incidence rates per 100,000 men were calculated and age-adjusted to 2000 US standard population. Annual percentage change (APC) was performed to identify the trend in prostate cancer incidence. RESULTS: Between 2008 and 2012, trends in incidence of overall and localized prostate cancer significantly declined in comparison with between 2000 and 2007 (APC, -5.4 and -6.0, respectively). However, there was an increase in the incidence rate of both overall and localized prostate cancer from 2014 to 2017 (43.3-46 and 34-34.9 per 100,000 men, respectively). The incidence of regional prostate cancer significantly increased between 2013 and 2017 (5.9-6.8 per 100,000 men; APC, 4.3). Distant disease incidence increased continually between 2008 and 2012 (2.9-3.3 per 100,000 men; APC, 2.3) and between 2013 and 2017 (3.4-4.3 per 100,000 men; APC, 6.0). In addition, these increases in incidence occurred in men of all stratified age and race/ethnicity groups, except for men aged <50 years and American Indian/Alaska Native men. CONCLUSION: This study demonstrates that the longer-term effects of USPSTF recommendations against PSA screening may have resulted in a reversal of downtrend in prostate cancer incidence, as incidence rates of overall and localized prostate cancer gradually increased from 2014 to 2017. Meanwhile, the trend in stage migration toward advanced disease increased incrementally.

An electric field immobilizes heavy metals through promoting combination with humic substances during composting.

The aim of this study was to explore a novel method to immobilize heavy metals (HM) in composting through increasing the combination of these with humic substances. An electric-field assistant technique was applied to strengthen biomass biodegradation and assess the impact on the humification process and HM immobilization in composting. Results demonstrated that the application of an electric field enriched bacterial abundance and enhanced bacterial metabolism. Humic substance and humic acid (HA) contents in compost product were significantly increased by 19 and 69%, respectively. The HA-complexed Cu, Zn, As, Cd contents were increased by 34, 41, 29 and 135.1%, respectively, which was attributed to the promotion of HA formation since a positive correlation between HA and HA-complexed HM (R2 = 0.60-0.87) was established. The evidence presented here supports the future development of electric field implementation as an intrinsic bioremediation technique for HM immobilization.

Ammonia emissions from different pig production scales and their temporal variations in the North China Plain.

Pig production systems in China are shifting from small to industrial scale. Significant variation in housing ammonia (NH3) emissions can exist due to differences in diet, housing design, and management practices. However, there is a knowledge gap regarding the impacts of farm-scale in China, which may be critical in identifying hotspots and mitigation targets. Here, continuous in-situ NH3 concentration measurements were made at pig farms of different scales for sows and fattening pigs over periods of 3-6 days during two different seasons (summer vs. winter). For the sow farms, NH3 emission rates were greater at the small farm (summer: 0.52 g pig-1 hr-1; winter: 0.21 g pig-1 hr-1) than at the large farm (summer: 0.34 g pig-1 hr-1; winter: 0.12 g pig-1 hr-1). For the fattening pig farms, NH3 emission rates were greater at the large farm (summer: 0.22 g pig-1 hr-1; winter: 0.16 g pig-1 hr-1) than at the small farm (summer: 0.19 g pig-1 hr-1; winter: 0.07 g pig-1 hr-1). Regardless of farm scale, the NH3 emission rates measured in summer were greater than those in winter; the NH3 emission rates were greater in the daytime than at the nighttime; a positive relationship (R2 = 0.06-0.68) was established between temperature and NH3 emission rate, whereas a negative relationship (R2 = 0.10-0.47) was found between relative humidity and NH3 emission rate. The effect of farm-scale on indoor NH3 concentration could mostly be explained by the differences in ventilation rates between farms. The diurnal variation in NH3 concentration could be partly explained by ventilation rate (R2 = 0.48-0.78) in the small traditional farms and by emission rate (R2 = 0.26-0.85) in the large industrial farms, except for the large fattening pig farm in summer. Overall, mitigation of NH3 emissions from sow farms should be a top priority in the North China Plain. Implications: The present study firstly examined the farm-scale effect of ammonia emissions in the North China Plain. Of all farms, the sow farm was identified as the greatest source of ammonia emission. Regardless of farm scale, ammonia emission rates were observed to be higher in summer. Ammonia concentrations were mostly higher in the large industrial farms partly due to lower ventilation rates than in the small traditional farms.

Identification of a six-gene metabolic signature predicting overall survival for patients with lung adenocarcinoma.

BACKGROUND: Lung cancer is the leading cause of cancer-related deaths worldwide. Lung adenocarcinoma (LUAD) is one of the main subtypes of lung cancer. Hundreds of metabolic genes are altered consistently in LUAD; however, their prognostic role remains to be explored. This study aimed to establish a molecular signature that can predict the prognosis in patients with LUAD based on metabolic gene expression. METHODS: The transcriptome expression profiles and corresponding clinical information of LUAD were obtained from The Cancer Genome Atlas and Gene Expression Omnibus databases. The differentially expressed genes (DEGs) between LUAD and paired non-tumor samples were identified by the Wilcoxon rank sum test. Univariate Cox regression analysis and the lasso Cox regression model were used to construct the best-prognosis molecular signature. A nomogram was established comprising the prognostic model for predicting overall survival. To validate the prognostic ability of the molecular signature and the nomogram, the Kaplan-Meier survival analysis, Cox proportional hazards model, and receiver operating characteristic analysis were used. RESULTS: The six-gene molecular signature (PFKP, PKM, TPI1, LDHA, PTGES, and TYMS) from the DEGs was constructed to predict the prognosis. The molecular signature demonstrated a robust independent prognostic ability in the training and validation sets. The nomogram including the prognostic model had a greater predictive accuracy than previous systems. Furthermore, a gene set enrichment analysis revealed several significantly enriched metabolic pathways, which suggests a correlation of the molecular signature with metabolic systems and may help explain the underlying mechanisms. CONCLUSIONS: Our study identified a novel six-gene metabolic signature for LUAD prognosis prediction. The molecular signature could reflect the dysregulated metabolic microenvironment, provide potential biomarkers for predicting prognosis, and indicate potential novel metabolic molecular-targeted therapies.

Key phosphorylation sites in GPCRs orchestrate the contribution of ß-Arrestin 1 in ERK1/2 activation.

ß-arrestins (ßarrs) are key regulators of G protein-coupled receptor (GPCR) signaling and trafficking, and their knockdown typically leads to a decrease in agonist-induced ERK1/2 MAP kinase activation. Interestingly, for some GPCRs, knockdown of ßarr1 augments agonist-induced ERK1/2 phosphorylation although a mechanistic basis for this intriguing phenomenon is unclear. Here, we use selected GPCRs to explore a possible correlation between the spatial positioning of receptor phosphorylation sites and the contribution of ßarr1 in ERK1/2 activation. We discover that engineering a spatially positioned double-phosphorylation-site cluster in the bradykinin receptor (B2 R), analogous to that present in the vasopressin receptor (V2 R), reverses the contribution of ßarr1 in ERK1/2 activation from inhibitory to promotive. An intrabody sensor suggests a conformational mechanism for this role reversal of ßarr1, and molecular dynamics simulation reveals a bifurcated salt bridge between this double-phosphorylation site cluster and Lys294 in the lariat loop of ßarr1, which directs the orientation of the lariat loop. Our findings provide novel insights into the opposite roles of ßarr1 in ERK1/2 activation for different GPCRs with a direct relevance to biased agonism and novel therapeutics.