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The coronavirus disease 2019 (COVID-19) pandemic has highlighted the importance of developing novel vaccines. An ideal vaccine should trigger an intense immune reaction without causing significant side effects. In this study we found that substitution of tryptophan located in the cores of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) protein structures with certain smaller amino acids resulted in variants with melting temperatures of 33–37 °C. An enzyme activity assay indicated that the proteolytic activity of the main proteinase (3CLpro) decreased sharply when the environmental temperature exceeded the melting temperature, implying that other protein variants may lose most of their functions under the same conditions. This finding suggests that a virus variant containing engineered proteins with melting temperatures of 33–37 °C may only be functional in the upper respiratory tract where the temperature is about 33 °C, but will be unable to invade internal organs, which maintain temperatures above 37 °C, thus making it possible to construct temperature-sensitive attenuated vaccines.

Abstract Background Researches have used intra-compartmental infusion and ballon tourniquest to create high intra-compartmental pressure in animal models of Acute Compartment Syndrome (ACS). However, due to the large differences in the modeling methods and the evaluation criteria of ACS, further researches of its pathophysiology and pathogenesis are hindered. Currently, there is no ideal animal model for ACS and this study aimed to establish a reproducible, clinically relevant animal model. Methods Blunt trauma and fracture were caused by the free falling of weights (0.5 kg, 1 kg, 2 kg) from a height of 40 cm onto the lower legs of rats, and the application of pressures of 100 mmHg, 200 mmHg, 300 mmHg and 400 mmHg to the lower limbs of rats using a modified pressurizing device for 6 h. The intra-compartmental pressure (ICP) and the pressure change (ΔP) of rats with single and combined injury were continuously recorded, and the pathophysiology of the rats was assessed based on serum biochemistry, histological and hemodynamic changes. Results The ΔP caused by single injury method of different weights falling onto the lower leg did not meet the diagnosis criteria for ACS (

Lagerstroemia indica is an important commercial tree known for the ornamental value. In this study, the complete chloroplast genome sequence of Lagerstroemia indica “Pink Velour” (Lagerstroemia “Pink Velour”) was 152,174 bp in length with a GC content of 39.50%. It contained 85 protein coding genes (PCGs), 37 tRNAs, and 8 rRNA genes. 207 simple sequence repeats (SSRs) and 31 codons with relative synonymous codon (RSCU)value > 1 were detected. Phylogenetic analysis divided 10 Lagerstroemia species into evolutionary branches of clade A and clade B. We conducted a comparative analysis of Lagerstroemia “Pink Velours” complete chloroplast genome with the genomes of six closely related Lagerstroemia species from different origins. The structural features of all seven species were similar, except for the deletion of ycf1 nucleobases at the JSA boundary. The large single-copy (LSC) and the small single-copy (SSC) had a higher sequence divergence than the IR region, and 8 genes that were highly divergent (trnK-UUU, petN, psbF, psbJ, ndhE, ndhD, ndhI, ycf1) had been identified and could be used as molecular markers in future studies. High nucleotide diversity was present in genes belonging to the photosynthesis category. Mutation of single nucleic acid was mainly influenced by codon usage. The value percentage of nonsynonymous substitutions (Ka) and synonymous substitutions (Ks) in 6 Lagerstroemia species revealed that more photosynthesis genes have Ka or Ks only in Lagerstroemia fauriei, Lagerstroemia limii, and Lagerstroemia subcostata. These advances will facilitate the breeding of closely related Lagerstroemia species and deepen understanding on climatic adaptation of Lagerstroemia plants.

Abstract Background Myocardial ischemia/reperfusion injury (MI/RI) is involved in a variety of pathological states for which there is no effective treatment exists. Shuangshen Ningxin (SSNX) capsule which is developed by Xiyuan Hospital, Chinese Academy of Traditional Chinese Medicine has been demonstrated to alleviate MI/RI, but its mechanism remains to be further elucidated. Methods The MI/RI miniature pigs model was constructed to assess the pharmacodynamics of SSNX by blocking the proximal blood flow of the left anterior descending branch of the cardiac coronary artery through an interventional balloon. The principal chemical compounds and potential targets of SSNX were screened by HPLC–MS and SwissTargetPrediction. The targets of MI/RI were identified based on Online Mendelian Inheritance in Man (OMIM) and GeneCards. Cytoscape 3.9.0 was applied to construct a protein–protein interaction (PPI) network, and Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed using metascape. To further validate the mechanism of SSNX, Molecular docking, Transmission electron microscopy, and Western blot analysis were used to test the effectiveness of targets in related pathways. Results Our results indicated that SSNX significantly improved cardiac function, attenuated myocardial I/R injury. Through network analysis, a total of 15 active components and 201 targets were obtained from SSNX, 75 of which are potential targets for the treatment of MI/RI. KEGG and MCODE analysis showed that SSNX is involved in the mitophagy signaling pathway, and ginsenoside Rg1, ginsenoside Rb1 and ginsenoside Rb2 are key components associated with the mitophagy. Further experimental results proved that SSNX protected mitochondrial structure and function, and significantly reduced the expression of mitophagy-related proteins PTEN-induced putative kinase 1 (PINK1), Parkin, FUN14 domain containing 1 (FUNDC1) and Bcl-2/E1B-19 kDa interacting protein 3 (BNIP3) in MI/RI miniature pigs. Conclusion In our study, the integration of network pharmacology and experiments in vivo demonstrated that SSNX interfered with MI/RI by inhibiting mitophagy.

Abstract Acute kidney injury (AKI) is a common clinical dysfunction with complicated pathophysiology and limited therapeutic methods. Renal tubular injury and the following regeneration process play a vital role in the course of AKI, but the underlining molecular mechanism remains unclear. In this study, network-based analysis of online transcriptional data of human kidney found that KLF10 was closely related to renal function, tubular injury and regeneration in various renal diseases. Three classical mouse models confirmed the downregulation of KLF10 in AKI and its correlation with tubular regeneration and AKI outcome. The 3D renal tubular model in vitro and fluorescent visualization system of cellular proliferation were constructed to show that KLF10 declined in survived cells but increased during tubular formation or conquering proliferative impediment. Furthermore, overexpression of KLF10 significantly inhibited, whereas knockdown of KLF10 extremely promoted the capacity of proliferation, injury repairing and lumen-formation of renal tubular cells. In mechanism, PTEN/AKT pathway were validated as the downstream of KLF10 and participated in its regulation of tubular regeneration. By adopting proteomic mass spectrum and dual-luciferase reporter assay, ZBTB7A were found to be the upstream transcription factor of KLF10. Our findings suggest that downregulation of KLF10 positively contributed to tubular regeneration in cisplatin induced acute kidney injury via ZBTB7A-KLF10-PTEN axis, which gives insight into the novel therapeutic and diagnostical target of AKI.

Abstract Analyses of several databases showed that the lncRNA RNF157 Antisense RNA 1 (RNF157-AS1) is overexpressed in epithelial ovarian cancer (EOC) tissues. In our study, suppressing RNF157-AS1 strikingly reduced the proliferation, invasion, and migration of EOC cells compared with control cells, while overexpressing RNF157-AS1 greatly increased these effects. By RNA pulldown assays, RNA binding protein immunoprecipitation (RIP) assays, and mass spectrometry, RNF157-AS1 was further found to be able to bind to the HMGA1 and EZH2 proteins. Chromatin immunoprecipitation (ChIP) assays showed that RNF157-AS1 and HMGA1 bound to the ULK1 promoter and prevented the expression of ULK1. Additionally, RNF157-AS1 interacted with EZH2 to bind to the DIRAS3 promoter and diminish DIRAS3 expression. ULK1 and DIRAS3 were found to be essential for autophagy. Combination autophagy inhibitor and RNF157-AS1 overexpression or knockdown, a change in the LC3 II/I ratio was found using immunofluorescence (IF) staining and western blot (WB) analysis. The autophagy level also was confirmed by autophagy/cytotoxicity dual staining. However, the majority of advanced EOC patients require platinum-based chemotherapy, since autophagy is a cellular catabolic response to cell stress. As a result, RNF157-AS1 increased EOC cell sensitivity to chemotherapy and death under cis-platinum (DDP) treatment by suppressing autophagy, as confirmed by cell count Kit-8 (CCK8) assays, flow cytometry, and autophagy/cytotoxicity dual staining. Therefore, the OS and PPS times were longer in EOC patients with elevated RNF157-AS1 expression. RNF157-AS1-mediated autophagy has potential clinical significance in DDP chemotherapy for EOC patients.

Acute kidney injury (AKI) is a serious condition with high mortality. The most common cause is kidney ischemia/reperfusion (IR) injury, which is thought to be closely related to pyroptosis. Disulfiram is a well-known alcohol abuse drug, and recent studies have shown its ability to mitigate pyroptosis in mouse macrophages. This study investigated whether disulfiram could improve IR-induced AKI and elucidated the possible molecular mechanism. We generated an IR model in mouse kidneys and a hypoxia/reoxygenation (HR) injury model with murine tubular epithelial cells (MTECs). The results showed that IR caused renal dysfunction in mice and triggered pyroptosis in renal tubular epithelial cells, and disulfiram improved renal impairment after IR. The expression of proteins associated with the classical pyroptosis pathway (Nucleotide-binding oligomeric domain (NOD)-like receptor protein 3 (NLRP3), apoptosis-related specific protein (ASC), caspase-1, N-GSDMD) and nonclassical pyroptosis pathway (caspase-11, N-GSDMD) were upregulated after IR. Disulfiram blocked the upregulation of nonclassical but not all classical pyroptosis pathway proteins (NLRP3 and ASC), suggesting that disulfiram might reduce pyroptosis by inhibiting the caspase-11-GSDMD pathway. In vitro, HR increased intracellular ROS levels, the positive rate of PI staining and LDH levels in MTECs, all of which were reversed by disulfiram pretreatment. Furthermore, we performed a computer simulation of the TIR domain of TLR4 using homology modeling and identified a small molecular binding energy between disulfiram and the TIR domain. We concluded that disulfiram might inhibit pyroptosis by antagonizing TLR4 and inhibiting the caspase-11-GSDMD pathway.

Abstract Increasing evidence demonstrates that long noncoding RNAs (lncRNAs) play an important role in several pathogenic processes of the kidney. However, functions of lncRNAs in ischemic acute kidney injury (AKI) remain undefined. In this study, global lncRNA profiling indicated that many lncRNA transcripts were deregulated in kidney after ischemia reperfusion (IR). Among them, we identified IRAR (ischemia-reperfusion injury associated RNA) as a potential lncRNA candidate, which was mostly expressed by the tubular epithelial cells (TECs) after IR, involved in the development of AKI. GapmeR-mediated silencing and viral-based overexpression of IRAR were carried out to assess its function and contribution to IR-induced AKI. The results revealed that in vivo silencing of IRAR significantly reduced IR-induced proinflammatory cells infiltration and AKI. IRAR overexpression induced chemokine CCL2, CXCL1 and CXCL2 expression both in mRNA and protein levels in TECs, while, silencing of IRAR resulted in downregulation of these chemokines. RNA immunoprecipitation and RNA pulldown assay validated the association between IRAR and CCL2, CXCL1/2. Further examination revealed that specific ablation of CCL2 in TECs reduced macrophages infiltration and proinflammatory cytokine production, attenuated renal dysfunction in IR mice. Inhibition of CXC chemokine receptor 2 (receptor of CXCL1/2) reduced neutrofils infiltration, but had no overt effect on kidney function. To explore the mechanism of IRAR upregulation in kidney during IR, we analyzed promoter region of IRAR and predicted a potential binding site for transcription factor C/EBP β on IRAR promoter. Silencing of C/EBP β reduced IRAR expression in TECs. A dual-luciferase reporter assay and chromatin immunoprecipitation (ChIP) confirmed that IRAR was a transcriptional target of the C/EBP β. Altogether, our findings identify IRAR as a new player in the development of ischemic AKI through regulating chemokine production and immune cells infiltration, suggesting that IRAR is a potential target for prevention and/or attenuation of AKI.

Lipopolysaccharide (LPS)-induced septic acute kidney injury (AKI) is determined as a devastating organ dysfunction elicited by an inappropriate response to infection with high morbidity and mortality rates. Previous evidence has illustrated an indispensable role of mitochondrial aldehyde dehydrogenase 2 (ALDH2) in the pathogenesis of sepsis-induced multiorgan abnormalities. Specifically, this study investigated the potential role of ALDH2 in sepsis-induced AKI. After LPS administration, we observed a significant decline in renal function, increased inflammatory cytokines, oxidative stress, 4-hydroxy-2-nonenal (4-HNE) accumulation, and apoptosis via MAPK activation in ALDH2−/− mice; in contrast, pretreatment with Alda-1 (an ALDH2 activator) alleviated the LPS-induced dysfunctions in mice. Moreover, in vitro analysis revealed that ALDH2 overexpression in mouse tubular epithelial cells (mTECs) improved the inflammatory response, oxidative stress, 4-HNE accumulation, and apoptosis via MAPK inhibition, whereas ALDH2 knockdown in mTECs aggravated these parameters via MAPK activation. Therefore, ALDH2 may protect against LPS-induced septic AKI by suppressing 4-HNE/MAPK pathway.

Research have shown that sleep is associated with renal function. However, the potential effects of sleep duration or quality on kidney function in middle-aged and older Chinese adults with normal kidney function has rarely been studied. Our study aimed to investigate the association of sleep and kidney function in middle-aged and older Chinese adults. Four thousand and eighty six participants with an eGFR ≥60 ml/min/1.73 m2 at baseline were enrolled between 2011 and 2015 from the China Health and Retirement Longitudinal Study. Survey questionnaire data were collected from conducted interviews in the 2011. The eGFR was estimated from serum creatinine and/or cystatin C using the Chronic Kidney Disease Epidemiology Collaboration equations (CKD-EPI). The primary outcome was defined as rapid kidney function decline. Secondary outcome was defined as rapid kidney function decline with clinical eGFR of 8 h of night time sleep after adjustments for demographic, clinical, or psychosocial covariates. Furthermore, daytime nap did not present significant risk in both rapid eGFR decline or CKD development. In conclusion, sleep quality was significantly associated with the development of CKD in middle-aged and older Chinese adults with normal kidney function.

Leaf disc transformation is one of the traditional methods that are now widely used in chrysanthemum with highly economical and ornamental value in world flower production, but it depends on plant genotypes and is time consuming and complicated. In addition, the transformation success rate of this method is low, generally ranging from 0.1% to 6.25%. Therefore, a highly efficient transformation system is needed. In this study, we are the first to establish a high-efficient chrysanthemum Agrobacterium-mediated transformation system via vacuum infiltration. Chrysanthemum stem internode explants were used as research material and CmLEC1 was used as a reporter gene. After approximately 3 months of culture and selection, the positive transgenic plants were obtained. Additionally, the positive probability was about 42%. The transformation efficiency was up to 37.7%, and if the escapes were removed, it was 16%. Furthermore, stable expression of CmLEC1 in transgenic 'Yuhualuoying' was confirmed by qRT-PCR analysis. These results suggest that this genetic transformation system via vacuum infiltration of chrysanthemum stem internode is highly efficient and convenient, and much better than traditional leaf disc transformation, and it will play an important role in chrysanthemum transformation and functional genetics research.

Diabetic nephropathy (DN) contributes to increased morbidity and mortality among patients with diabetes and presents a considerable global health challenge. However, reliable biomarkers of DN have not yet been established. Phosphorylated proteins are crucial for disease progression. However, their diagnostic potential remains unexplored. In this study, we used ultra-high-sensitivity quantitative phosphoproteomics to identify phosphoproteins in urinary extracellular vesicles (uEVs) as potential biomarkers of DN. We detected 233 phosphopeptides within the uEVs, with 47 phosphoproteins exhibiting significant alterations in patients with DN compared to those in patients with diabetes. From these phosphoproteins, we selected phosphorylated aquaporin-2 (p-AQP2[S256]) and phosphorylated glycogen synthase kinase-3β (p-GSK3β[Y216]) for validation, as they were significantly overrepresented in pathway analyses and previously implicated in DN pathogenesis. Both phosphoproteins were successfully confirmed through Phos-tag western blotting in uEVs and immunohistochemistry staining in kidney sections, suggesting that phosphoprotein alterations in uEVs reflect corresponding changes within the kidney and their potential as candidate biomarkers for DN. Our research proposes the utilization of phosphoproteins in uEVs as a liquid biopsy, presenting a highly feasible diagnostic tool for kidney disease.

Summary: TWIK-related acid-sensitive K+ channel-2 (TASK-2, encoded by Kcnk5) is essential in cell biological processes, by regulating transmembrane K+ balance. In the present study, we aimed to clarify the role of TASK-2 in renal fibrosis and explore the underlying mechanism. We found that TASK-2 level was elevated in the renal tubular UUO- and UIR-induced renal fibrosis as well as in patients with renal tubulointerstitial fibrosis. Knockout of Kcnk5 or inhibition of TASK-2 in renal tubules attenuated G2/M cell-cycle arrest and alleviated renal fibrosis. Mechanistically, demethylase fat mass and obesity-associated protein (FTO) reduced N6-adenosine methylation (m6A) of Kcnk5 mRNA following renal fibrosis. FTO deficiency attenuated the upregulation of TASK-2 and renal fibrosis. The results demonstrated the crucial role of TASK-2 in renal fibrosis, which is conducive to a better understanding of the pathogenesis of renal fibrosis. TASK-2 may be a potential treatment strategy to alleviate the development of renal fibrosis.

Background: Acute kidney injury (AKI) is a common clinical syndrome with limited methods of treatment and diagnosis. Although several molecules associated with AKI have been discovered, molecular mechanisms underlying AKI still remain unclear. Weighted gene co-expression network analysis (WGCNA) is a novel method to uncover the relationship between co-expression genes and clinical traits at the system level.Methods: First, by employing WGCNA in transcriptional data on 30 patients with well/poor functioning kidney graft, we identified two co-expression modules that were significantly related to serum creatinine (SCr). Second, based on the modules, potential small molecular compound candidates for developing targeted therapeutics were obtained by connectivity map analysis. Furthermore, multiple validations of expression in space/time were carried out with two classical AKI models in vivo and other five databases of over 152 samples.Results: Two of the 14 modules were found to be closely correlated with SCr. Function enrichment analysis illustrated that one module was enriched in the immune system, while the other was in the metabolic process. Six key renal function-related genes (RFRGs) were finally obtained. Such genes performed well in cisplatin-induced or cecal ligation and puncture-induced AKI mouse models.Conclusion: The analysis suggests that WGCNA is a proper method to connect clinical traits with genome data to find novel targets in AKI. The kidney tissue with worse renal function tended to develop a “high immune but low metabolic activity” expression pattern. Also, ACSM2A, GLYAT, CORO1A, DPEP1, ALDH7A1, and EPHX2 are potential targets of molecular diagnosis and treatment in AKI.

Aristolochic acid nephropathy (AAN) is a type of drug-induced nephropathy and is correlated with a potentially progression of kidney fibrosis. However, whether miR-382 is implicated in macrophage activation in AA-induced kidney fibrosis remains elusive. Here, cell-sorting experiments defined a significant miR-382 enrichment in renal macrophage after AAN 14 days. Then, we found that treatment of AA induced a significant switch in the phenotype of macrophage both in vivo and in vitro. Furthermore, miR-382 knockout (KO) mice and miR-382-/- bone marrow-derived macrophage (BMDM) were subjected to AA induction. We found that both systemic KO and macrophage-specific miR-382 depletion notably suppressed M2-like macrophage activation as well as kidney interstitial fibrosis. Additionally, adoptive transfer of miR-382 overexpression BMDMs into mice promoted AA-induced kidney injury. Moreover, in cultured macrophage, upregulation of miR-382 promoted M2-related gene expression, accompanied by downregulation of signal regulatory protein α (SIRP-α) and activation of signal transducer and activator of transcription 3 (STAT3). The interaction between miR-382 and SIRP-α was evaluated via dual-luciferase assay. Knockdown of SIRP-α upregulated phosphorylated STAT3 at S727 and Y705. Pharmacological inhibition of STAT3 was performed both in vivo and in vitro. Inhibition of STAT3 attenuated AA-induced kidney fibrosis, in parallel to lesser macrophage M2 polarization. Coculture experiments further confirmed that overexpressed miR-382 in macrophage promoted injuries of tubular cells. Luminex bio-chip detection suggested that IL-4 and CCL-5 were critical in the cross talk between macrophages and tubular cells. Taken together, our data suggest that miR-382 is a critical mediator in M2-like macrophage polarization and can be a promising therapeutic target for kidney fibrosis.

S genes are the key genes that cause plant self-incompatibility, to find out the key S genes and understand molecular mechanism of self-incompatibility in chrysanthemum, the stigmas and anthers at different developmental stages of 'Q10-22-2'—a self-incompatible chrysanthemum cultivar, were used for RNA sequencing. After bioinformatics analysis, 13 candidate pistil S genes and five candidate pollen S genes were excavated. A potential pistil S gene was cloned and named as CmSRK1. Meanwhile, a potential pollen S gene was cloned and named as CmPCP1. qRT-PCR revealed that CmSRK1 was specifically expressed in mature stigmas, and CmPCP1 was specifically expressed in anthers 3 d before maturation. Subcellular localization showed that both CmSRK1 and CmPCP1 were located in the nucleus and the cell membrane. Transcriptional activation activity analysis indicated that both of the two proteins had no transcriptional activation activity. Yeast two hybrid assay showed that there was no interaction between CmSRK1 and CmPCP1. CmSRK1 was constructed on the expression vector containing stigma-specific promoter, and CmPCP1 was constructed on the expression vector containing pollen-specific promoter, they were then transformed into Arabidopsis thaliana. Artificial hybridization was performed with transgenic lines containing CmSRK1 as the female parents, and transgenic lines containing CmPCP1 as the male parents. The hybridization results showed that seed sets of two transgenic lines were 19.62% and 11.64%, respectively, while cross-pollinated seed sets of Col-0 was 84.43%. Therefore, it was speculated that CmSRK1 and CmPCP1 might be pistil and pollen S genes of chrysanthemum, respectively, and SI of chrysanthemum belonged to SSI.

Abstract Background Fluid overload is related to the development and prognosis of cardiac surgery-associated acute kidney injury (CSA-AKI). The study is to investigate the influence of serum creatinine (SCr) corrected by fluid balance on the prognosis of patients with cardiac surgery. Methods A retrospective study was conducted in 1334 patients who underwent elective cardiac surgery from January 1 to December 31, 2015. Kidney Disease: Improving Global Outcomes (KDIGO) criteria for AKI were applied to identify CSA-AKI. SCr was measured every 24 h during ICU period and was accordingly adjusted for cumulative fluid balance. Changes in SCr, defined as ∆Crea, were determined by difference between before and after adjustment for cumulative fluid balance. All patients were then divided into three groups: underestimation group (∆Crea ≥ P75), normal group (P25

Abstract Background We aimed to investigate the relationship between the perioperative hemodynamic parameters and the occurrence of cardiac surgery-associated acute kidney injury. Methods A retrospective study was performed in patients who underwent cardiac surgery at a tertiary referral teaching hospital. Acute kidney injury was determined according to the KDIGO criteria. We investigated the association between the perioperative hemodynamic parameters and cardiac surgery-associated acute kidney injury to identify the independent hemodynamic predictors for acute kidney injury. Subgroup analysis was further performed in patients with chronic hypertension. Results Among 300 patients, 29.3% developed acute kidney injury during postoperative intensive care unit period. Multivariate logistic analysis showed the postoperative nadir diastolic perfusion pressure, but not mean arterial pressure, central venous pressure and mean perfusion pressure, was independently linked to the development of acute kidney injury after cardiac surgery (odds ratio 0.945, P = 0.045). Subgroup analyses in hypertensive subjects (n = 91) showed the postoperative nadir diastolic perfusion pressure and peak central venous pressure were both independently related to the development of acute kidney injury (nadir diastolic perfusion pressure, odds ratio 0.886, P = 0.033; peak central venous pressure, odds ratio 1.328, P = 0.010, respectively). Conclusions Postoperative nadir diastolic perfusion pressure was independently associated with the development of cardiac surgery-associated acute kidney injury. Furthermore, central venous pressure should be considered as a potential hemodynamic target for hypertensive patients undergoing cardiac surgery.

Background: Uncoupling protein 1 (UCP1) is predominantly found in brown adipose tissue mitochondria, and mediates energy dissipation to generate heat rather than ATP via functional mitochondrial uncoupling. However, little is known about its expression and function in kidney. Methods: We carried out a mRNA microarray analysis in mice kidneys with ischemia reperfusion (IR) injury. The most dramatically downregulated gene UCP1 after IR was identified, and its role in generation of mitochondrial reactive oxygen species (ROS) and oxidative stress injury was assessed both in vitro and in vivo. Genetic deletion of UCP1 was used to investigate the effects of UCP1 on ischemia or cisplatin-indued acute kidney injury (AKI) in mice. Findings: UCP1 was located in renal tubular epithelial cells in kidney and downregulated in a time-dependent manner during renal IR. Deletion of UCP1 increased oxidative stress in kidneys and aggravated ischemia or cisplatin induced AKI in mice.Viral-based overexpression of UCP1 reduced mitochondrial ROS generation and apoptosis in hypoxia-treated tubular epithelial cells. Furthermore, UCP1 expression was regulated by peroxisome proliferator-activator receptor (PPAR) γ in kidneys during renal IR. Overexpression of PPAR-γ resembled UCP1-overexpression phenotype in vitro. Treatment with PPAR-γ agonist could induce UCP1 upregulation and provide protective effect against renal IR injury in UCP1+/+mice, but not in UCP1−/−mice. Interpretation: UCP1 protects against AKI likely by suppressing oxidative stress, and activation of UCP1 represents a potential therapeutic strategy for AKI. Fund: National Natural Science Foundation of China grants, Science and Technology Commission of Shanghai. Keywords: Acute kidney injury, Uncoupling protein 1, Reactive oxygen species, Peroxisome proliferator-activator receptor γ

Billions of people suffer from dental caries every year in spite of the effort to reduce the prevalence over the past few decades. Streptococcus mutans is the leading member of a specific group of cariogenic bacteria that cause dental caries. S. mutans forms biofilm, which is highly resistant to harsh environment, host immunity, and antimicrobial treatments. In this study, we found that S. mutans biofilm is highly resistant to both antimicrobial agents and lysozyme. DexA70, the truncated form of DexA (amino acids 100–732), a dextranase in S. mutans, prevents S. mutans biofilm formation and disassembles existing biofilms within minutes at nanomolar concentrations when supplied exogenously. DexA70 treatment markedly enhances biofilm sensitivity to antimicrobial agents and lysozyme, indicating its great potential in combating biofilm-related dental caries.

Functional lilies are a group of edible lily cultivars with great potential for landscape application. Low-temperature storage can significantly improve their taste, but the knowledge of this process is largely unknown. In this study, we used the functional lilies ‘Fly Shaohua’ and ‘Fly Tiancheng’ as materials. Through physiological observation and transcriptome analysis during the bulbs’ cold storage, it was found that the starch degradation and sucrose accumulation in bulbs contributed to taste improvement. After 60 d of cold storage, the sucrose accumulation was highest and the starch content was lower in the bulbs, suggesting this time-point was optimal for consumption. Accompanying the fluctuation of sucrose content during cold storage, the enzyme activities of sucrose phosphate synthase and sucrose synthase for sucrose synthesis were increased. Transcriptome analysis showed that many differentially expressed genes (DEGs) were involved in the starch and sucrose metabolism pathway, which might promote the conversion of starch to sucrose in bulbs. In addition, the DEGs involved in dormancy and stress response were also determined during cold storage, which might explain the decreased sucrose accumulation with extended storage time over 60 d due to the energy consumption for dormancy release. Taken together, our results indicated sucrose accumulation was a main factor in the taste improvement of lily bulbs after cold storage, which is attributable to the different gene expression of starch and sucrose metabolism pathways in this process.

Renal ischemia-reperfusion (I/R) can induce oxidative stress and injury via the generation of reactive oxygen species (ROS). Renal proximal tubular cells are susceptible to oxidative stress, and the dysregulation of renal proximal tubular cellular homeostasis can damage cells via apoptotic pathways. A recent study showed that the generation of ROS can increase perilipin 2 (Plin2) expression in HepG2 cells. Some evidence has also demonstrated the association between Plin2 expression and renal tumors. However, the underlying mechanism of Plin2 in I/R-induced acute kidney injury (AKI) remains elusive. Here, using a mouse model of I/R-induced AKI, we found that ROS generation was increased and the expression of Plin2 was significantly upregulated. An in vitro study further revealed that the expression of Plin2, and the generation of ROS were significantly upregulated in primary tubular cells treated with hydrogen peroxide. Accordingly, Plin2 knockdown decreased apoptosis in renal proximal tubular epithelial cells treated with hydrogen peroxide, which depended on the activation of peroxisome proliferator-activated receptor α (PPARα). Overall, the present study demonstrated that Plin2 is involved in AKI; knockdown of this marker might limit apoptosis via the activation of PPARα. Consequently, the downregulation of Plin2 could be a novel therapeutic strategy for AKI.

A glycosyl hydrolase produced by Pseudomonas aeruginosa, PslG, has become a promising candidate for biofilm treatment because of its ability to inhibit and disperse biofilms by disrupting exopolysaccharide matrix at nanomolar concentrations. However, as a protein, PslG used for treatment may be degraded by the ubiquitous proteases (of which trypsin-like serine proteases are a major group) secreted by human cells. This would lead to an insufficient effective concentration of PslG. Here, based on the result of liquid chromatography–tandem mass spectrometry (LC-MS/MS) and structural analysis, we generate a PslG mutant (K286A/K433S) with greatly enhanced trypsin resistance. This measure raises IC50 (the concentration of trypsin that can degrade 50% of protein in 30 min at 37°C) from 0.028 mg mL–1 of the wild-type PslG to 0.283 mg mL–1 of PslGK286A/K433S. In addition, biofilm inhibition assay shows that PslGK286A/K433S is much more efficient than wild-type PslG in the presence of trypsin. This indicates that PslGK286A/K433S is a better biofilm inhibitor than wild-type PslG in clinical use where trypsin-like proteases widely exist.

The virulence factor pyocyanin and the second messenger c-di-GMP regulate biofilm formation and antibiotic tolerance in Pseudomonas aeruginosa. Here, the authors perform structural and biochemical analyses to show that a transcriptional regulator, BrlR, acts as a receptor for both pyocyanin and c-di-GMP.

Background/Aims: Ovarian endometriosis (OvE) is ovarian cyst that is lined with endometrial tissue. They are found in 17–44% of women with endometriosis. Their clinical manifestations include pelvic pain, dysmenorrhea, dyspareunia, and infertility. Although the incidence of OvE has increased yearly, the exact pathogenesis of OvE is still unclear. We used peptidomics, an emerging branch of proteomics, to identify differentially expressed peptides in order to determine the possible roles of these peptides in the pathogenesis of OvE. Methods: The ectopic and eutopic endometria of OvE were used to extract peptides with 10-kDa molecular weight cutoff filters, and the peptide precursor proteins were then identified with PEAKS software, followed by quantification with the TMT labeling method and subsequent analysis by liquid chromatography-tandem mass spectrometry. Gene ontology (GO) analysis, pathway analysis, SMART, and SABLE were used to study the possible functions of these peptide according to their precursor proteins’ function. The effects of peptides derived from VCAM-1 (PDFV) on endometrial stromal cell (ESC) migration and invasion were examined with wound healing assays and Transwell assays and the expression of E-cadherin was detected by western blotting. Results: A total of 491 peptides were identified with abundant differences between the two groups of samples (p < 0.05, and absolute fold change ≥ 2). SMART and SABLE database showed that 42 of the 491 peptides were located in the conserved structural domains of their protein precursors and contained secondary structure and, among them, 2 peptides’ precursor proteins were associated with the cell proliferation. Additionally, 5 peptides’ precursor proteins were associated with endometriosis. Our study confirmed that PDFV promoted ESC migration and invasion and reduced E-cadherin expression (p < 0.05). Conclusion: PDFV and its precursor protein VCAM-1 may be involved in the process of OvE formation by reducing the expression of E-cadherin. The peptidomics analysis provides new insight for future studies of the mechanisms of OvE development.

Dibenzothiophene (DBT) and their derivatives, accounting for the major part of the sulfur components in crude oil, make one of the most significant pollution sources. The DBT sulfone monooxygenase BdsA, one of the key enzymes in the “4S” desulfurization pathway, catalyzes the oxidation of DBT sulfone to 2′-hydroxybiphenyl 2-sulfonic acid (HBPSi). Here, we determined the crystal structure of BdsA from Bacillus subtilis WU-S2B, at the resolution of 2.2 Å, and the structure of the BdsA-FMN complex at 2.4 Å. BdsA and the BdsA-FMN complex exist as tetramers. DBT sulfone was placed into the active site by molecular docking. Seven residues (Phe12, His20, Phe56, Phe246, Val248, His316, and Val372) are found to be involved in the binding of DBT sulfone. The importance of these residues is supported by the study of the catalytic activity of the active site variants. Structural analysis and enzyme activity assay confirmed the importance of the right position and orientation of FMN and DBT sulfone, as well as the involvement of Ser139 as a nucleophile in catalysis. This work combined with our previous structure of DszC provides a systematic structural basis for the development of engineered desulfurization enzymes with higher efficiency and stability.

MicroRNAs (miRNAs), around 22 nucleotides (nt) in length, are a class of endogenous and noncoding RNA molecule that play an essential role in plant development, either by suppressing the transcription of target genes at a transcriptional level or inhibiting translation at a posttranscriptional level. To understand the roles of miRNAs and their target genes in chrysanthemum polyploidy breeding, three sRNA libraries of normal and abnormal embryos after hybridization were performed by RNA-Seq. As a result, a total of 170 miRNAs were identified and there are 41 special miRNAs in cross of paternal chromosome doubling, such as miR169b, miR440, and miR528-5p. miR164c and miR159a were highly expressed in a normal embryo at 18 days after pollination, suggesting the regulatory role at the late stage of embryonic development. miR172c was only detected in the normal embryo at 18 days after pollination, which means that miR172c mainly mediates gene expression in postembryonic development and these genes may promote embryo maturation. Other miRNAs, including miR414, miR2661, and miR5021, may regulate the genes participated in pathways of auxin response and energy metabolism; then they regulate the complex embryonic development together.

An urban fringe area, depicted as a typical ecotone, is a region where both social and environmental problems are concentrated. Identifying and evaluating the spatial–temporal characteristics of urban fringe areas is significant for future development. On the basis of the land use data extracted from remote sensing data, the Shannon diversity index (SHDI) of each unit can be calculated, and identifying the urban fringe area by the breakpoint method is reliable. By using the rapidly growing Changchun as example, this study identifies the urban fringe of Changchun in 1995, 2005, and 2015 by applying the breakpoint method. The expansion amount, change mode, direction of expansion, landscape, and influence factors are evaluated. Policy and planning are the main factors influencing the development direction of the Changchun fringe area. The urban fringe area of Changchun City is extended to the east, southeast, and north. From 1995 to 2005, the outlying expansion was the dominant type. The main change mode was the infilling type due to the reduction of available land, from 2005 to 2015. In accordance with the landscape metrics, the landscape within the urban fringe transformed from fragmentation to regularization. The development of the urban fringe also transformed from a disorderly to an orderly manner.

The intracellular pathogen Legionella pneumophila hijacks the endoplasmic reticulum (ER)-derived vesicles to create an organelle designated Legionella-containing vacuole (LCV) required for bacterial replication. Maturation of the LCV involved acquisition of Rab1, which is mediated by the bacterial effector protein SidM/DrrA. SidM/DrrA is a bifunctional enzyme having the activity of both Rab1-specific GDP dissociation inhibitor (GDI) displacement factor (GDF) and guanine nucleotide exchange factor (GEF). LidA, another Rab1-interacting bacterial effector protein, was reported to promote SidM/DrrA-mediated recruitment of Rab1 to the LCV as well. Here we report the crystal structures of LidA complexes with GDP- and GTP-bound Rab1 respectively. Structural comparison revealed that GDP-Rab1 bound by LidA exhibits an active and nearly identical conformation with that of GTP-Rab1, suggesting that LidA can disrupt the switch function of Rab1 and render it persistently active. As with GTP, LidA maintains GDP-Rab1 in the active conformation through interaction with its two conserved switch regions. Consistent with the structural observations, biochemical assays showed that LidA binds to GDP- and GTP-Rab1 equally well with an affinity approximately 7.5 nM. We propose that the tight interaction with Rab1 allows LidA to facilitate SidM/DrrA-catalyzed release of Rab1 from GDIs. Taken together, our results support a unique mechanism by which a bacterial effector protein regulates Rab1 recycling.