Functionally Collaborative Nanostructure for Direct Monitoring of Neurotransmitter Exocytosis in Living Cells.

Neurotransmitter exocytosis of living cells plays a vital role in neuroscience. However, the available amperometric technique with carbon fiber electrodes typically measures exocytotic events from one cell during one procedure, which requires professional operations and takes time to produce statistical results of multiple cells. Here, we develop a functionally collaborative nanostructure to directly measure the neurotransmitter dopamine (DA) exocytosis from living rat pheochromocytoma (PC12) cells. The functionally collaborative nanostructure is constructed of metal-organic framework (MOF)-on-nanowires-on-graphene oxide, which is highly sensitive to DA molecules and enables direct detection of neurotransmitter exocytosis. Using the microsensor, the exocytosis from PC12 cells pretreated with the desired drugs (e.g., anticoronavirus drug, antiflu drug, or anti-inflammatory drug) has been successfully measured. Our achievements demonstrate the feasibility of the functionally collaborative nanostructure in the real-time detection of exocytosis and the potential applicability in the highly efficient assessment of the modulation effects of medications on exocytosis.

Alternative splicing of chitin deacetylase 2 regulates chitin and fatty acid metabolism in Asian citrus psyllid, Diaphorina citri.

Chitin plays an important role in the development and molting of insects. The key genes involved in chitin metabolism were considered promising targets for pest control. In this study, two splice variants of chitin deacetylase 2 (CDA2) from Diaphorina citri were identified, including DcCDA2a and DcCDA2b. Bioinformatics analysis revealed that DcCDA2a and DcCDA2b encoded 550 and 544 amino acid residues with a signal peptide, respectively. Spatio-temporal expression patterns analysis showed that DcCDA2a and DcCDA2b were highly expressed in D. citri wing and nymph stages. Moreover, DcCDA2a and DcCDA2b expression levels were induced by 20-hydroxyecdysone (20E). Silencing DcCDA2a by RNA interference (RNAi) significantly disrupted the D. citri molting and increased D. citri mortality and malformation rate, whereas inhibition of DcCDA2b resulted in a semimolting phenotype. Furthermore, silencing DcCDA2a and DcCDA2b significantly suppressed D. citri chitin and fatty acid metabolism. Our results indicated that DcCDA2 might play crucial roles in regulating D. citri chitin and fatty acid metabolism, and it could be used as a potential target for controlling D. citri.

Natural Coumarin Shows Toxicity to Spodoptera litura by Inhibiting Detoxification Enzymes and Glycometabolism.

Coumarin and its derivatives are plant-derived compounds that exhibit potent insecticidal properties. In this study, we found that natural coumarin significantly inhibited the growth and development of Spodoptera litura larvae through toxicological assay. By transcriptomic sequencing, 80 and 45 differentially expressed genes (DEGs) related to detoxification were identified from 0 to 24 h and 24 to 48 h in S. litura after coumarin treatment, respectively. Enzyme activity analysis showed that CYP450 and acetylcholinesterase (AChE) activities significantly decreased at 48 h after coumarin treatment, while glutathione S-transferases (GST) activity increased at 24 h. Silencing of SlCYP324A16 gene by RNA interference significantly increased S. litura larval mortality and decreased individual weight after treatment with coumarin. Additionally, the expression levels of DEGs involved in glycolysis and tricarboxylic acid (TCA) cycle were inhibited at 24 h after coumarin treatment, while their expression levels were upregulated at 48 h. Furthermore, metabonomics analysis identified 391 differential metabolites involved in purine metabolism, amino acid metabolism, and TCA cycle from 0 to 24 h after treated with coumarin and 352 differential metabolites associated with ATP-binding cassette (ABC) transporters and amino acid metabolism. These results provide an in-depth understanding of the toxicological mechanism of coumarin on S. litura.

Antibody-Based Methods Reveal the Protein Expression Properties of Glucosinolate Sulfatase 1 and 2 in Plutella xylostella.

The glucosinolates (GLs) and myrosinase defensive systems in cruciferous plants were circumvented by Plutella xylostella using glucosinolate sulfatases (PxGSSs) during pest-plant interaction. Despite identifying three duplicated GSS-encoding genes in P. xylostella, limited information regarding their spatiotemporal and induced expression is available. Here, we investigated the tissue- and stage-specific expression and induction in response to GLs of PxGSS1 and PxGSS2 (PxGSS1/2) at the protein level, which shares a high degree of similarity in protein sequences. Western blotting (WB) analysis showed that PxGSS1/2 exhibited a higher protein level in mature larvae, their guts, and gut content. A significantly high protein and transcript levels of PxGSS1/2 were also detected in the salivary glands using WB and qRT-PCR. The immunofluorescence (IF) and immunohistochemistry (IHC) results confirmed that PxGSS1/2 is widely expressed in the larval body. The IHC was more appropriate than IF when autofluorescence interference was present in collected samples. Furthermore, the content of PxGSS1/2 did not change significantly under treatments of GL mixture from Arabidopsis thaliana ecotype Col-0, or commercial ally (sinigrin), 4-(methylsulfinyl)butyl, 3-(methylsulfinyl)propyl, and indol-3-ylmethyl GLs indicating that the major GLs from leaves of A. thaliana Col-0 failed to induce the expression of proteins for both PxGSS1 and PxGSS2. Our study systemically characterized the expression properties of PxGSS1/2 at the protein level, which improves our understanding of PxGSS1/2-center adaptation in P. xylostella during long-term insect-plant interaction.

Silencing of Glycogen Synthase Kinase 3 Significantly Inhibits Chitin and Fatty Acid Metabolism in Asian Citrus Psyllid, Diaphorina citri.

Glycogen is a predominant carbohydrate reserve in various organisms, which provides energy for different life activities. Glycogen synthase kinase 3 (GSK3) is a central player that catalyzes glucose and converts it into glycogen. In this study, a GSK3 gene was identified from the D. citri genome database and named DcGSK3. A reverse transcription quantitative PCR (RT-qPCR) analysis showed that DcGSK3 was expressed at a high level in the head and egg. The silencing of DcGSK3 by RNA interference (RNAi) led to a loss-of-function phenotype. In addition, DcGSK3 knockdown decreased trehalase activity, glycogen, trehalose, glucose and free fatty acid content. Moreover, the expression levels of the genes associated with chitin and fatty acid synthesis were significantly downregulated after the silencing of DcGSK3. According to a comparative transcriptomics analysis, 991 differentially expressed genes (DEGs) were identified in dsDcGSK3 groups compared with dsGFP groups. A KEGG enrichment analysis suggested that these DEGs were primarily involved in carbon and fatty acid metabolism. The clustering analysis of DEGs further confirmed that chitin and fatty acid metabolism-related DEGs were upregulated at 24 h and were downregulated at 48 h. Our results suggest that DcGSK3 plays an important role in regulating the chitin and fatty acid metabolism of D. citri.

miR-124 regulates liver cancer stem cells expansion and sorafenib resistance.

Liver cancer stem cells (CSCs) contribute to tumorigenesis, progression, recurrence and drug resistance of hepatocellular carcinoma (HCC). However, the underlying mechanism for liver CSCs expansion remains unclear. Herein, we report that miR-124 is downregulated in liver CSCs and associated with the poor prognosis of HCC. Functional studies revealed that a forced expression of miR-124 inhibits liver CSCs self-renew and tumorigenesis. Conversely, miR-124 knockdown promotes liver CSCs self-renew and tumorigenesis. Mechanistically, miR-124 directly target Caveolin-1 (CAV1) via its mRNA 3'UTR in liver CSCs. Furthermore, miR-124 expression determines the responses of hepatoma cells to sorafenib treatment. The analysis of patient cohort and patient-derived xenografts (PDXs) further demonstrated that miR-124 may predict sorafenib benefits in HCC patients. In conclusion, our findings revealed the crucial role of the miR-124 in liver CSCs expansion and sorafenib response, rendering miR-124 an optimal target for the prevention and intervention in HCC.

Region-Wide Comprehensive Implementation of Roguing Infected Trees, Tree Replacement, and Insecticide Applications Successfully Controls Citrus Huanglongbing.

Huanglongbing (HLB) is a devastating citrus disease worldwide. A three-pronged approach to controlling HLB has been suggested, namely, removal of HLB-symptomatic trees, psyllid control, and replacement with HLB-free trees. However, such a strategy did not lead to successful HLB control in many citrus-producing regions, such as Florida. We hypothesize that this is because of the small-scale or incomprehensive implementation of the program; conversely, a comprehensive implementation of such a strategy at the regional level can successfully control HLB. To test our hypothesis, we investigated the effects of region-wide comprehensive implementation of this scheme to control HLB in Gannan region, China, with a total planted citrus acreage of over 110,000 ha from 2013 to 2019. With the region-wide implementation of comprehensive HLB management, the overall HLB incidence in Gannan decreased from 19.71% in 2014 to 3.86% in 2019. A partial implementation of such a program (without a comprehensive inoculum removal) at the regional level in Brazil resulted in HLB incidence increasing from 1.89% in 2010 to 19.02% in 2019. Using dynamic regression model analyses with data from both Brazil and China, we constructed a model to predict HLB incidence when all three components were applied at 100%. It was predicated that in a region-wide comprehensive implementation of such a program, HLB incidence would be controlled to a level of less than 1%. We conducted economic feasibility analyses and showed that average net profits were positive for groves that implemented the comprehensive strategy, but groves that did not implement it had negative net profits over a 10-year period. Overall, the key for the three-pronged program to successfully control HLB is the large scale (region-wide) and comprehensiveness in implementation. This study provides valuable information to control HLB and other economically important endemic diseases worldwide.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Postoperative serum triglyceride levels in predicting risk of new-onset diabetes mellitus in patients following liver transplantation.

To investigate the postoperative serum triglyceride (TG) levels in predicting the risk of new-onset diabetes mellitus (NODM) in patients following allogeneic liver transplantation. One hundred and forty three patients undergoing allogeneic liver transplantation in Shanghai General Hospital from July 2007 to July 2014 were enrolled in this study. The NODM developed in 33 patients after liver transplantation. The curve of dynamic TG levels in the early period after liver transplantation was generated. Independent risk factors of NODM were determined by univariate and multivariant logistic regression analyses. The clinical value of TG in predicting NODM was analyzed by area under the ROC curve (AUC). Serum TG levels were gradually rising in the first week and then reached the plateau phase (stable TG, sTG) in patients after surgery. The sTG in NODM group were significantly higher than that in non-NODM group (=-2.31, <0.05). Glucocorticoid therapy (=4.054, <0.01), FK506 drug concentration in the first week after operation (=3.482, <0.05) and sTG (=3.156, <0.05) were independent risk factors of NODM. ROC curve analysis showed that the AUC of sTG in predicting NODM was 0.72. TG shows a gradual recovery process in the early period after liver transplantation, and the higher TG level in stable phase may significantly increase the risk of NODM in patients.

Restoration of p53 acetylation by HDAC inhibition permits the necrosis/apoptosis switch of pancreatic ainar cell during experimental pancreatitis in mice.

The severity of acute pancreatitis (AP) is greatly attributed to the pancreatic acinar cell (PAC) death response. It has been established that the apoptosis-inducing therapy can protect against experimental pancreatitis and have great clinical therapeutic potential. However, current pharmacologic agents that target apoptosis during AP largely lack specificity. Thus, it remains imperative to reveal the specific mechanisms governing acinar cell death. Death responses of PAC are manifested by the progressive necrosis accompanied by apoptosis silencing during AP in mice. In this study, we found that the transcriptional activity of p53 was impaired and the expressions of its proapoptotic targets Puma and CD95 were significantly decreased, which explains the apoptosis silencing during AP. Furthermore, we found that the functional depression of p53 was resulted from histone deacetylase (HDAC)-mediated deacetylation of p53 C-terminal in PAC during AP. Treatment of the HDAC inhibitor trichostatin-A restored p53 apoptosis pathway, resulted in a necrosis/apoptosis switch and protected mice from cerulein- or l-Arg-induced AP. Our research identified the HDAC-dependent regulation of p53 activity as a critical mechanism underlying acinar cell death response, which represents a specific target for the treatment of AP.

Identification and functional analysis of an iron-binding protein, ferritin heavy chain subunit, from the swallowtail butterfly, Papilio xuthus.

Ferritin, which is ubiquitous among all living organisms, plays a crucial role in maintaining iron homeostasis, immune response, and detoxification. In the present research, we identified an iron-binding protein, ferritin heavy chain subunit, from Papilio xuthus and named PxFerHCH. The complete complementary DNA of PxFerHCH was 1,252 bp encoding a sequence of 211 amino acids, which includes an iron-responsive element. Phylogenetic analysis showed that PxFerHCH is clustered with Manduca sexta and Galleria mellonella ferritin heavy chain subunits. Expression levels of PxFerHCH in various tissues were analyzed by reverse transcription quantitative polymerase chain reaction, and the results exhibited that PxFerHCH was expressed in all tissues with the highest expression in the fat body. The relative expression level of PxFerHCH in response to bacterial (Escherichia coli and Staphylococcus aureus) challenges sharply increased by about 12 hr postinfection (hpi) and then decreased at 24 hpi. In addition, the iron-binding capacity and antioxidation activity of recombinant PxFerHCH protein were also investigated. These results reveal that PxFerHCH might play an important role in defense against bacterial infection.

Immune Functional Analysis of Chitin Deacetylase 3 from the Asian Citrus Psyllid Diaphorina citri.

Chitin deacetylase (CDA) is a chitin degradation enzyme that strictly catalyzes the deacetylation of chitin to form chitosan, which plays an important role in regulating growth and development, as well as the immune response. In this study, a chitin deacetylase 3 gene (CDA3) was identified with a complete open reading frame (ORF) of 1362 bp from the genome database of Diaphorina citri, encoding a protein of 453 amino acids. Spatiotemporal expression analysis suggested that D. citri CDA3 (DcCDA3) had the highest expression level in the integument and third-instar nymph stage. Furthermore, DcCDA3 expression level can be induced by 20-hydroxyecdysone (20E). Injection of Escherichia coli and Staphylococcus aureus induced the upregulation of DcCDA3 in the midgut, while DcCDA3 was downregulated in the fat body. After silencing DcCDA3 by RNA interference, there was no influence on the D. citri phenotype. In addition, bactericidal tests showed that recombinant DcCDA3 inhibited gram-positive bacteria, including S. aureus and Bacillus subtilis (B. subtilis). In conclusion, our results suggest that DcCDA3 might play an important role in the immune response of D. citri.

Silencing of the Chitin Synthase Gene Is Lethal to the Asian Citrus Psyllid, Diaphorina citri.

Chitin synthase is a critical enzyme that catalyzes N-acetylglucosamine to form chitin, which plays an important role in the growth and development of insects. In this study, we identified a chitin synthase gene (CHS) with a complete open reading frame (ORF) of 3180 bp from the genome database of Diaphorina citri, encoding a protein of 1059 amino acid residues with the appropriate signature motifs (EDR and QRRRW). Reverse transcription-quantitative PCR (RT-qPCR) analysis suggested that D. citri CHS (DcCHS) was expressed throughout all developmental stages and all tissues. DcCHS had the highest expression level in the integument and fifth-instar nymph stage. Furthermore, the effects of diflubenzuron (DFB) on D. citri mortality and DcCHS expression level were investigated using fifth-instar nymph through leaf dip bioassay, and the results revealed that the nymph exposed to DFB had the highest mortality compared with control group (Triton-100). Silencing of DcCHS by RNA interference resulted in malformed phenotypes and increased mortality with decreased molting rate. In addition, transmission electron microscopy (TEM) and fluorescence in situ hybridization (FISH) also revealed corresponding ultrastructural defects. Our results suggest that DcCHS might play an important role in the development of D. citri and can be used as a potential target for psyllid control.

[Anti-inflammatory effect of interleukin-35 in mice with colitis and its mechanism].

OBJECTIVE: To investigate the anti-inflammatory effect and mechanisms of interleukin-35 (IL-35) in inflammatory bowel disease. METHODS: BALB/c mice were divided into three groups with 10 mice in each group:control group, model group (oral administration of 4% glucan sodium sulfate for 7 d) and IL-35-treated group (oral administration of 4% glucan sodium sulfate for 7 d, intraperitoneal injection of 2 µg IL-35 at d2-5). Disease activity index (DAI) was scored every day. After 7 d, the mice were sacrificed, and the serum and intestinal tissue samples were collected. The gross morphology of the colon was observed; HE staining was used to observe the pathological changes of colon tissue; flow cytometry was employed to detect the change of macrophage polarization ratio in colon tissue; the mRNA expression levels of cytokines IL-6, TNF-α, IFN-γ, IL-10 and SHIP1 in colon tissue were determined by real-time quantitative RT-PCR; the expression and distribution of SHIP1 in colon tissue was measured by immunohistochemistry; Western blotting was adopted to detect the expression level of SHIP1 protein in colonic intestinal tissues of each group. RESULTS: The DAI scores of the mice in the model group were higher than those in the control group, while the DAI scores in the IL-35-treated group were lower than those in the model group (all P<0.01). Compared with the control group, the colon length was significantly shortened in the model group (P<0.05), while the colon length of the IL-35-treated group had an increasing trend compared with the model group, but the difference was not statistically significant (P>0.05). Compared with the model group, microscopic inflammatory infiltration score was decreased and microscopic crypt destruction and score was significantly lower in IL-35-treated group (all P<0.05). The relative expression of proinflammatory cytokines IL-6, TNF-α and IFN-γ in the colon tissue of IL-35-treated group was decreased compared with the model group, while the relative expression of IL-10 mRNA was higher than that of the model group (all P<0.05). Compared with the control group, the proportion of M1 macrophages in the model group increased (P<0.05), while the proportion of M1 macrophages in the IL-35-treated group was lower than that in the model group (P<0.05). The relative expression of SHIP1 mRNA and protein in the colon tissue of IL-35-treated group was higher than that in the model group (all P<0.05). CONCLUSIONS: IL-35 can inhibit the polarization of M1 macrophages and regulate inflammatory cytokines to promote anti-inflammatory effect on mice with colitis.

Efficacy and Safety of Single-Balloon Versus Double-Balloon Enteroscopy: A Single-Center Retrospective Analysis.

BACKGROUND Single-balloon endoscopy (SBE) has been introduced as a simplified endoscopy technique after the promotion of double-balloon endoscopy (DBE). The difference in clinical performance between DBE and SBE is still not very clear. In this study, we aimed to compare the efficacy and safety between these 2 endoscopic procedures. MATERIAL AND METHODS A total of 173 patients with suspected small bowel disease were enrolled into this study from January 2007 to December 2011. All cases were divided into DBE or SBE groups according to the endoscopic procedures they underwent. We then compared the diagnostic yield, the influence of DBE and SBE on the diagnostic/therapeutic course, the examination time, and post-procedure discomfort between DBE and SBE groups. RESULTS We observed no notable adverse events during or after the examinations. Additionally, SBE displays a significantly higher diagnostic rate (62.0%) than DBE (35.6%) via the anal approach (P=0.0137), while there was no difference in positive diagnostic rate between DBE and SBE via the oral route. Remarkably, it takes significantly less time to perform SBE examinations (38.86±5.64 minutes) than DBE procedures (41.80±6.50 minutes) via the oral route (P=0.048), although the average examination time for DBE is close to that for SBE via the anal route (P=0.952). However, DBE and SBE are similar in terms of their impact on the diagnostic/therapeutic course and complication rate. CONCLUSIONS Both SBE and DBE are very safe procedures to perform and SBE is a preferred choice for the evaluation of small bowel diseases in terms of diagnostic rate via the anal route compared with DBE.

Down-regulation of microRNA-155 attenuates retinal neovascularization via the PI3K/Akt pathway.

PURPOSE: We aimed to investigate the anti-angiogenic properties of miR-155 via in vitro and in vivo studies. METHODS: miR-155 was knocked down using lentivirus-mediated RNA interference. The proliferation, migration, and tube formation of human retinal microvascular endothelial cells (HRMECs) were measured using BrdU, Transwell, and Matrigel assays, respectively. An oxygen-induced retinopathy (OIR) model was induced using neonatal C57BL/6J pups. Anti-miR-155 was intravitreally injected on postnatal day 12, and the retinal non-perfused areas and extent of neovascularization were measured on postnatal day 18 using transcardiovascular fluorescein isothiocyanate (FITC)-dextran perfusion and retina sections. A laser-induced choroidal neovascularization (CNV) model was induced in adult C57BL/6J mice. To evaluate the leakage areas, fundus fluorescein angiography was performed on day 14 after anti-miR-155 intravitreal injection. The neovascularization area of the CNV model was also examined in confocal and retina section studies. The expression levels of SHIP1 and p-Akt (Thr308, Ser473, and Thr450) were evaluated both in vitro and in vivo. RESULTS: The expression of miR-155 was elevated in HRMECs after treatment with vascular endothelial growth factor (VEGF) and in neovascularized mouse model retinas. Anti-miR-155 lentivirus reduced the VEGF-induced proliferation, migration, and tube formation abilities of HRMECs. Anti-miR-155 attenuated retinal neovascularization in in vivo CNV and OIR models. In VEGF-treated HRMECs and retina neovascularization models, p-Akt (Ser473) was significantly upregulated, while SHIP1 was downregulated. Conversely, the inhibition of miR-155 restored the expression of SHIP1 and reduced the phosphorylation of effectors in the Akt (Ser473) signaling pathway. CONCLUSIONS: The results revealed that the downregulation of miR-155 attenuated retinal neovascularization via the phosphatidylinositol 3-kinase (PI3K)/Akt pathway.

Efficacy and safety of adalimumab for the Crohn's disease: a systematic review and meta-analysis of published randomized placebo-controlled trials.

PURPOSE: The aim of this study was to evaluate the efficacy and safety of adalimumab (ADA) for Crohn's disease. METHODS: Electronic databases, including PubMed, Embase, the Cochrane Library, and the Science Citation Index, were searched to retrieve relevant trials. We estimated pooled estimates of the odds ratio (OR) and relevant 95% confidence interval (CI) using fixed effects model or random effects model as appropriate. RESULTS: Six randomized placebo-controlled studies met the selection criteria. Short-term clinical response/remission and long-term remission were better in the ADA groups than in the control groups (P < 0.05), both in anti-TNF-naive patients and in subjects who lost their response and/or became intolerant to infliximab (IFX). And ADA was also effective for patients who were previously treated with IFX, and its efficacy in infliximab-exposed patients was probably less than in infliximab-naive patients. In patients with active Crohn's disease (CD), ADA therapy was more effective than placebo for obtaining complete fistula closure. In comparison with placebo, ADA does not increase the risk of serious adverse events. CONCLUSIONS: ADA appears to be effective in achieving short-term clinical response/remission, long-term remission, and complete fistula healing in CD, including patients not manageable with IFX, and appears to have a favorable safety profile. A longer duration of follow-up and a larger number of patients are required to better assess the safety profile of ADA in CD.

5-Azacytidine accelerates mandarin fruit post-ripening and enhances lignin-based pathogen defense through remarkable gene expression activation.

5-Azacytidine (AZ) is a DNA methylation inhibitor that has recently demonstrated potential in regulating fruit quality through exogenous application. In this study, we treated mandarin fruits for 4-day storage. Noteworthy were the induced degreening and the enhanced citrus aroma of fruits under AZ treatment, involving the promotion of chlorophyll degradation, carotenoid biosynthesis, and limonene biosynthesis. Key genes associated with these processes exhibited expression level increases of up to 123.8 times. Additionally, AZ treatment activated defense-related enzymes and altered phenylpropanoid carbon allocation towards lignin biosynthesis instead of flavonoid biosynthesis. The expression levels of lignin biosynthesis-related genes increased by nearly 100 times, leading to fortified lignin that is crucial for citrus defense against Penicillium italicum. Currently, the underlying mechanisms of such intense AZ-induced changes in gene expressions remain unclear and further research could help establish AZ treatment as a viable strategy for citrus preservation.

Serratia marcescens induces apoptosis in Diaphorina citri gut cells via reactive oxygen species-mediated oxidative stress.

BACKGROUND: Asian citrus psyllid, Diaphorina citri, is a notorious pest in the citrus industry because it transmits Candidatus Liberibacter asiaticus, which causes an uncurable, devastating disease in citrus worldwide. Serratia marcescens is widely distributed in various environments that exhibits toxic effects to many insects. To develop strategies for enhancing the efficiency of pathogen-induced host mortality, a better understanding of the toxicity mechanism of Serratia marcescens on Diaphorina citri is critical. RESULTS: Serratia marcescens KH-001 successfully colonized Diaphorina citri gut by feeding artificial diets, resulting in the damage of cells including nucleus, mitochondria, vesicles, and microvilli. Oral ingestion of Serratia marcescens KH-001 strongly induced apoptosis in gut cells by enhancing levels of Cyt c, p53 and caspase-1 and decreasing levels of inhibitors of apoptosis (IAP) and Bax inhibitor-1 (BI-1). The expression of dual oxidase (Duox) and nitric oxide synthase (Nos) was up-regulated by Serratia marcescens KH-001, which increased hydrogen peroxide (H2 O2 ) levels in the gut. Injection of abdomen of Diaphorina citri with H2 O2 accelerated the death of the adults and induced apoptosis in the gut cells by activating Cyt c, p53 and caspase-1 and suppressing IAP and BI-1. Pretreatment of infected Diaphorina citri with vitamin c (Vc) increased the adult survival and diminished the apoptosis-inducing effect. CONCLUSIONS: The colonization of Serratia marcescens KH-001 in the guts of Diaphorina citri increased H2 O2 accumulation, leading to severe changes and apoptosis in intestinal cells, which enhanced a higher mortality level of D. citr. This study identifies the underlying virulence mechanism of Serratia marcescens KH-001 on Diaphorina citri that contributes to a widespread application in the integrated management of citrus psyllid. © 2023 Society of Chemical Industry.

C-X-C Motif Chemokine Ligand 1 Promotes Colitis by Modulating the Gut Microbiota.

INTRODUCTION: C-X-C motif chemokine ligand 1 (CXCL1) is a potent neutrophil chemoattractant that plays a pivotal role in recruiting neutrophils during inflammatory conditions. This study explored the role of CXCL1 in modulating the gut microbiota, influencing neutrophil infiltration, and contributing to the development of colitis. METHODS: We employed quantitative PCR to assess CXCL1 expression in colon samples. A mouse model of dextran sulfate sodium (DSS)-induced colitis was utilized to explore the progression of colitis in wild-type (WT) and CXCL1-deficient (CXCL1-/-) mice. RESULTS: Colitis attenuation was evident in CXCL1-/- mice. Significant alterations were observed in the gut microbiome, as revealed by 16S rRNA gene sequencing. Furthermore, CXCL1-/- mice exhibited reduced gut permeability and diminished endotoxin levels in peripheral blood following DSS treatment compared to WT mice. In response to DSS treatment, WT mice showed a clear increase in neutrophil infiltration, while CXCL1-/- mice exhibited lower levels of infiltration. Fecal microbiota transplantation (FMT) using stools from CXCL1-/- mice alleviated DSS-induced colitis. Interestingly, FMT from patients with colitis increased CXCL1 and Ly6G expression in the colons of gut-sterilized mice. Clinical data analysis revealed elevated CXCL1 and CD15 expression in patients with colitis, with a positive correlation between the severity of colitis and the expression of CXCL1 and CD15. CONCLUSION: These findings shed light on the pivotal role of CXCL1 in promoting colitis by modulating the gut microbiota.

A Combinatorial Single-Molecule Real-Time and Illumina Sequencing Analysis of Postembryonic Gene Expression in the Asian Citrus Psyllid Diaphorina citri.

Huanglongbing (HLB) is a systemic plant disease caused by 'Candidatus Liberibacter asiaticus (CLas)' and transmitted by Diaphorina citri. D. citri acquires the CLas bacteria in the nymph stage and transmits it in the adult stage, indicating that molting from the nymph to adult stages is crucial for HLB transmission. However, the available D. citri reference genomes are incomplete, and gene function studies have been limited to date. In the current research, PacBio single-molecule real-time (SMRT) and Illumina sequencing were performed to investigate the transcriptome of D. citri nymphs and adults. In total, 10,641 full-length, non-redundant transcripts (FLNRTs), 594 alternative splicing (AS) events, 4522 simple sequence repeats (SSRs), 1086 long-coding RNAs (lncRNAs), 281 transcription factors (TFs), and 4459 APA sites were identified. Furthermore, 3746 differentially expressed genes (DEGs) between nymphs and adults were identified, among which 30 DEGs involved in the Hippo signaling pathway were found. Reverse transcription-quantitative PCR (RT-qPCR) further validated the expression levels of 12 DEGs and showed a positive correlation with transcriptome data. Finally, the spatiotemporal expression pattern of genes involved in the Hippo signaling pathway exhibited high expression in the D. citri testis, ovary, and egg. Silencing of the D. citri transcriptional co-activator (DcYki) gene significantly increased D. citri mortality and decreased the cumulative molting. Our results provide useful information and a reliable data resource for gene function research of D. citri.