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1.
Aquat Toxicol ; 272: 106979, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38823072

ABSTRACT

Tris(2-chloroethyl) phosphate (TCEP) and tris(1­chloro-2-propyl) phosphate (TCPP) are widely used as chlorinated organophosphate flame retardants (OPFRs) due to their fire-resistance capabilities. However, their extensive use has led to their permeation and pollution in aquatic environments. Using amphibians, which are non-model organisms, to test the toxic effects of OPFRs is relatively uncommon. This study examined the acute and chronic toxicity differences between TCEP and TCPP on Polypedates megacephalus tadpoles and evaluated the potential ecological risks to tadpoles in different aquatic environments using the risk quotient (RQ). In acute toxicity assay, the tadpole survival rates decreased with increased exposure time and concentrations, with TCEP exhibiting higher LC50 values than TCPP, at 305.5 mg/L and 70 mg/L, respectively. In the chronic assay, prolonged exposure to 300 µg/L of both substances resulted in similar adverse effects on tadpole growth, metamorphosis, and hepatic antioxidant function. Based on RQ values, most aquatic environments did not pose an ecological risk to tadpoles. However, the analysis showed that wastewater presented higher risks than rivers and drinking water, and TCPP posed a higher potential risk than TCEP in all examined aquatic environments. These findings provide empirical evidence to comprehend the toxicological effects of OPFRs on aquatic organisms and to assess the safety of aquatic environments.

2.
Phys Rev Lett ; 132(20): 207101, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38829089

ABSTRACT

Nonequilibrium thermal machines under cyclic driving generally outperform steady-state counterparts. However, there is still lack of coherent understanding of versatile transport and fluctuation features under time modulations. Here, we formulate a theoretical framework of thermodynamic geometry in terms of full counting statistics of nonequilibrium driven transports. We find that, besides the conventional dynamic and adiabatic geometric curvature contributions, the generating function is also divided into an additional nonadiabatic contribution, manifested as the metric term of full counting statistics. This nonadiabatic metric generalizes recent results of thermodynamic geometry in near-equilibrium entropy production to far-from-equilibrium fluctuations of general currents. Furthermore, the framework proves geometric thermodynamic uncertainty relations of near-adiabatic thermal devices, constraining fluctuations in terms of statistical metric quantities and thermodynamic length. We exemplify the theory in experimentally accessible driving-induced quantum chiral transport and Brownian heat pump.

3.
World J Gastrointest Surg ; 16(4): 1195-1202, 2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38690044

ABSTRACT

BACKGROUND: Percutaneous transhepatic stent placement has become a common strategy for the postoperative treatment of portal vein (PV)/superior mesenteric veins (SMV) stenosis/occlusion. It has been widely used after liver transplantation surgery; however, reports on stent placement for acute PV/SMV stenosis after pancreatic surgery within postoperative 3 d are rare. CASE SUMMARY: Herein, we reported a case of intestinal edema and SMV stenosis 2 d after pancreatic surgery. The patient was successfully treated using stent grafts. Although the stenosis resolved after stent placement, complications, including bleeding, pancreatic fistula, bile leakage, and infection, made the treatment highly challenging. The use of anticoagulants was adjusted multiple times to prevent venous thromboembolism and the risk of bleeding. After careful treatment, the patient stabilized, and stent placement effectively managed postoperative PV/SMV stenosis. CONCLUSION: Stent placement is effective and feasible for treating acute PV/SMV stenosis after pancreatic surgery even within postoperative 3 d.

4.
Heart Lung ; 67: 53-61, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38701700

ABSTRACT

BACKGROUND: The association between coffee and caffeine intake and the risk of COPD and lung function has not been thoroughly discussed in Americans, with subgroup and threshold effects remaining unclear. OBJECTIVES: This study investigated the association between coffee and caffeine consumption and the risk of chronic obstructive pulmonary disease (COPD) as well as lung function utilizing data from the NHANES 2007-2012. METHODS: We assessed the associations of coffee and caffeine consumption with the risk of COPD and lung function parameters, including FEV1 and FVC, adjusting for common demographic and disease characteristics in a cross-sectional analysis of NHANES data. RESULTS: A total of 9763 participants were included in the study, and 592 were diagnosed with COPD. Multivariate regression models revealed positive associations between coffee and caffeine consumption and the risk of COPD and lung function. Subgroup analyses stratified by sex, DM, hypertension status, and smoking habits identified potential effect modifiers as well as inflection points from threshold effect examinations. CONCLUSIONS: The results of this cross-sectional study indicated significant positive correlations between coffee and caffeine consumption and the risk of COPD. Additionally, positive correlations between exposure variables and FEV1 and FVC were detected. Among the stratification factors, smoking status exhibited the most potential for modifying effects. Future practices and research are needed to validate the results and explore the underlying mechanisms.

6.
Nat Prod Res ; : 1-5, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38721687

ABSTRACT

A new triterpenoid compound 1* (scandine A1) was obtained from 95% ethanol extract of Uncaria laevigata. Meanwhile, eleven described compounds were also isolated for the first time from Uncaria laevigata. Herein, compound 2 exhibited strong diastolic cardio-cerebrovascular activity (EC50BA = 9.22 µM and EC50CA = 14.65 µM), which was not been previously described. Compound 1* also showed certain diastolic cardio-cerebrovasculary activity. Network pharmacology indicated that the diastolic cardio-cerebrovascular activity of compound 2 was most correlated with the Ras signalling pathway. Molecular docking confirmed that it exhibited strong binding activity with target protein (matrix metalloproteinase inhibitor-1). Moreover, compound 2 demonstrated significant potential on cardio-cerebrovascular activity in vitro. Overall, compounds 1* and 2 with good diastolic cardio-cerebrovascular activity were discovered in this work.

7.
iScience ; 27(5): 109738, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38706844

ABSTRACT

Tumor tissues often contain high extracellular adenosine, promoting an immunosuppressed environment linked to mesenchymal transition and immune evasion. Here, we show that loss of the epithelial transcription factor, GRHL2, triggers NT5E/CD73 ecto-enzyme expression, augmenting the conversion of AMP to adenosine. GRHL2 binds an intronic NT5E sequence and is negatively correlated with NT5E/CD73 in breast cancer cell lines and patients. Remarkably, the increased adenosine levels triggered by GRHL2 depletion in MCF-7 breast cancer cells do not suppress but mildly increase CD8 T cell recruitment, a response mimicked by a stable adenosine analog but prevented by CD73 inhibition. Indeed, NT5E expression shows a positive rather than negative association with CD8 T cell infiltration in breast cancer patients. These findings reveal a GRHL2-regulated immune modulation mechanism in breast cancers and show that extracellular adenosine, besides its established role as a suppressor of T cell-mediated cytotoxicity, is associated with enhanced T cell recruitment.

8.
Front Microbiol ; 15: 1324209, 2024.
Article in English | MEDLINE | ID: mdl-38741737

ABSTRACT

Background: A mounting body of evidence suggests a strong connection between gut microbiota and the risk of frailty. However, the question of causality remains unanswered. In this study, we employed a Mendelian randomization (MR) approach to assess potential causal relationships between gut microbiota and the risk of frailty. Materials and methods: Summary statistics for the gut microbiome were obtained from a genome wide association study (GWAS) meta-analysis of the MiBioGen consortium (N = 18,340). Summary statistics for frailty were obtained from a GWAS meta-analysis, including the UK Biobank and TwinGene (N = 175,226). Our primary analysis utilized the inverse variance weighted (IVW) method. To enhance the robustness of our results, we also applied weighted median methods, MR Egger regression, and MR pleiotropy residual sum and outlier test. Finally, we conducted reverse MR analysis to investigate the potential for reverse causality. Results: IVW method identified 7 bacterial taxa nominally associated with the risk of FI. Class Bacteroidia (p = 0.033) and genus Eubacterium ruminantium group (p = 0.028) were protective against FI. In addition, class Betaproteobacteria (p = 0.042), genus Allisonella (p = 0.012), genus Bifidobacterium (p = 0.013), genus Clostridium innocuum group (p = 0.036) and genus Eubacterium coprostanoligenes group (p = 0.003) were associated with a higher risk of FI. No pleiotropy or heterogeneity were found. Conclusion: The MR analysis indicates a causal relationship between specific gut microbiota and FI, offering new insights into the mechanisms underlying FI mediated by gut microbiota.

9.
Toxicol Lett ; 2024 May 09.
Article in English | MEDLINE | ID: mdl-38734219

ABSTRACT

Humantenmine, koumine, and gelsemine are three indole alkaloids found in the highly toxic plant Gelsemium. Humantenmine was the most toxic, followed by gelsemine and koumine. The aim of this study was to investigate and analyze the effects of these three substances on tissue distribution and toxicity in mice pretreated with the Cytochrome P450 3A4 (CYP3A4) inducer ketoconazole and the inhibitor rifampicin. The in vivo test results showed that the three alkaloids were absorbed rapidly and had the ability to penetrate the blood-brain barrier. At 5minutes after intraperitoneal injection, the three alkaloids were widely distributed in various tissues and organs, the spleen and pancreas were the most distributed, and the content of all tissues decreased significantly at 20minutes. Induction or inhibition of CYP3A4 in vivo can regulate the distribution and elimination effects of the three alkaloids in various tissues and organs. Additionally, induction of CYP3A4 can reduce the toxicity of humantenmine, and vice versa. Changes in CYP3A4 levels may account for the difference in toxicity of humantenmine. These findings provide a reliable and detailed dataset for drug interactions, tissue distribution, and toxicity studies of Gelsemium alkaloids.

10.
Commun Biol ; 7(1): 583, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38755265

ABSTRACT

Tumor-associated macrophages of the M2 phenotype promote cancer initiation and progression. Importantly, M2 macrophage-derived exosomes play key roles in the malignancy of cancer cells. Here, we report that circTMCO3 is upregulated in ovarian cancer patients, and its high expression indicates poor survival. M2-derived exosomes promote proliferation, migration, and invasion in ovarian cancer, but these effects are abolished by knockdown of circTMCO3. Furthermore, circTMCO3 functions as a competing endogenous RNA for miR-515-5p to reduce its abundance, thus upregulating ITGA8 in ovarian cancer. miR-515-5p inhibits ovarian cancer malignancy via directly downregulating ITGA8. The decreased oncogenic activity of circTMCO3-silencing exosomes is reversed by miR-515-5p knockdown or ITGA8 overexpression. Exosomal circTMCO3 promotes ovarian cancer progression in nude mice. Thus, M2 macrophage-derived exosomes promote malignancy by delivering circTMCO3 and targeting the miR-515-5p/ITGA8 axis in ovarian cancer. Our findings not only provide mechanistic insights into ovarian cancer progression, but also suggest potential therapeutic targets.


Subject(s)
Exosomes , Mice, Nude , MicroRNAs , Ovarian Neoplasms , Female , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Ovarian Neoplasms/metabolism , Humans , Exosomes/metabolism , Exosomes/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , Animals , Mice , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Macrophages/metabolism , RNA, Circular/genetics , RNA, Circular/metabolism , Cell Proliferation , Integrin alpha Chains/genetics , Integrin alpha Chains/metabolism , Cell Movement
11.
Perioper Med (Lond) ; 13(1): 41, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38755693

ABSTRACT

BACKGROUND: Postoperative delirium is a common complication in older patients, with poor long-term outcomes. This study aimed to investigate risk factors and develop a predictive model for postoperative delirium in older patients after major abdominal surgery. METHODS: This study retrospectively recruited 7577 patients aged ≥ 65 years who underwent major abdominal surgery between January 2014 and December 2018 in a single hospital in Beijing, China. Patients were divided into a training cohort (n = 5303) and a validation cohort (n = 2224) for univariate and multivariate logistic regression analyses and to build a nomogram. Data were collected for 43 perioperative variables, including demographics, medical history, preoperative laboratory results, imaging, and anesthesia information. RESULTS: Age, chronic obstructive pulmonary disease, white blood cell count, glucose, total protein, creatinine, emergency surgery, and anesthesia time were associated with postoperative delirium in multivariate analysis. We developed a nomogram based on the above 8 variables. The nomogram achieved areas under the curve of 0.731 and 0.735 for the training and validation cohorts, respectively. The discriminatory ability of the nomogram was further assessed by dividing the cases into three risk groups (low-risk, nomogram score < 175; medium-risk, nomogram score 175~199; high-risk, nomogram score > 199; P < 0.001). Decision curve analysis revealed that the nomogram provided a good net clinical benefit. CONCLUSIONS: We developed a nomogram that could predict postoperative delirium with high accuracy and stability in older patients after major abdominal surgery.

12.
Clin Nutr ESPEN ; 61: 316-321, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38777450

ABSTRACT

INTRODUCTION: Osteoporosis and osteopenia, together known as low bone mineral density (LBMD), are common problems in the elderly. LBMD may cause fragility fractures in the elderly. The relationship between Vitamin E and LBMD in old Americans is still unclear. In this study, we investigated the relationship between serum Vitamin E levels and LBMD in the elderly. METHODS: We utilized data from the National Health and Nutrition Examination Survey (NHANES) 2017-2018 and ultimately included 378 participants aged 50 to 79. Multivariable logistic or linear regression models were applied to examine the associations between serum Vitamin E levels and LBMD, total femur or lumbar spine BMD after adjusting for covariates. RESULTS: After adjusting for all covariates, higher serum Vitamin E levels reduced the risk of LBMD (OR 0.76; 95% CI 0.58-1.00) and were positively associated with total femur BMD (ß: 0.02; 95% CI: 0.01-0.03), after adjusting for all covariates. In the subgroup analysis, for the BMI normal group (BMI<25), the serum Vitamin E levels were positively associated with the total femur (ß: 0.03; 95% CI: 0.01-0.05) and lumbar spine BMD (ß: 0.04; 95% CI: 0.01-0.07). In the BMI normal group, people with high serum Vitamin E levels have a lower incidence of LBMD (OR:0.43; 95% CI: 0.21-0.88). Though the P for interaction was larger than 0.05. CONCLUSION: This study found serum Vitamin E levels were negatively associated with LBMD in older Americans. Serum Vitamin E levels were positively associated with femur BMD in older Americans.


Subject(s)
Bone Density , Nutrition Surveys , Osteoporosis , Vitamin E , Humans , Vitamin E/blood , Aged , Female , Male , Cross-Sectional Studies , Middle Aged , Osteoporosis/blood , Lumbar Vertebrae , Risk Factors , Femur , Bone Diseases, Metabolic/blood , Bone Diseases, Metabolic/epidemiology
13.
Biomed Pharmacother ; 176: 116760, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38788595

ABSTRACT

With the increasing prevalence of metabolic disorders, hyperglycemia has become a common risk factor that endangers people's lives and the need for new drug solutions is burgeoning. Trans-2, 4-dimethoxystilbene (TDMS), a synthetic stilbene, has been found as a novel hypoglycemic small molecule from glucose consumption test. Normal C57BL/6 J mice, mouse models of type 1 diabetes mellitus and diet-induced obesity subjected to TDMS gavage were found with lower glycemic levels and better glycemic control. TDMS significantly improved the symptoms of polydipsia and wasting in type 1 diabetic mice, and could rise their body temperature at the same time. It was found that TDMS could promote the expression of key genes of glucose metabolism in HepG2, as do in TDMS-treated liver, while it could improve the intestinal flora and relieve intestinal metabolic dysbiosis in hyperglycemic models, which in turn affected its function in the liver, forming the gut-liver axis. We further fished PPARγ by virtual screening that could be promoted by TDMS both in-vitro and in-vivo, which was regulated by upstream signaling of AMPKα phosphorylation. As a novel hypoglycemic small molecule, TDMS was proven to be promising with its glycemic improvements and amelioration of diabetes symptoms. It promoted glucose absorption and utilization by the liver and improved the intestinal flora of diabetic mice. Therefore, TDMS is expected to become a new hypoglycemic drug that acts through gut-liver axis via AMPKα-PPARγ signaling pathway in improving glycemic metabolism, bringing new hope to patients with diabetes and glucose metabolism disorders.

14.
Ecotoxicol Environ Saf ; 278: 116336, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38691883

ABSTRACT

Aflatoxin B1 (AFB1), a common mycotoxin, can occur in agricultural products. As a metabolite of AFB1, aflatoxin M1 (AFM1) mainly exist in dairy products. These two mycotoxins threaten human health, although it is unclear how they affect the function of the intestinal barrier. In this study, mice were exposed to AFB1 (0.3 mg/kg body b.w.) and AFM1(3.0 mg/kg b.w.) either individually or in combination for 28 days to explore the main differentially expressed proteins (DEPs) and the associated enriched pathways. These findings were preliminarily verified by the transcriptomic and proteomic analyses in differentiated Caco-2 cells. The results revealed that AFB1 and AFM1 exposure in mice disrupted the function of the intestinal barrier, and the combined toxicity was greater than that of each toxin alone. Further proteomic analysis in mice demonstrated that the mechanisms underlying these differences could be explained as follows: (i) lipid metabolism was enriched by AFB1-induced DEPs. (ii) protein export pathway was stimulated by AFM1-induced DEPs. (iii) cell metabolic ability was inhibited (as evidenced by changes in UDP-GT1, UDP-GT2, and Gatm6), apoptosis was induced (MAP4K3), and epithelial cell integrity was disrupted (Claudin7 and IQGAP2), resulting in more extensive intestinal damage after combined treatment. In conclusion, the hazardous impact of co-exposure to AFB1 and AFM1 from proteomic perspectives was demonstrated in the present study.


Subject(s)
Aflatoxin B1 , Aflatoxin M1 , Proteomics , Aflatoxin M1/toxicity , Aflatoxin B1/toxicity , Animals , Mice , Caco-2 Cells , Humans , Male , Intestines/drug effects , Intestines/pathology , Intestinal Mucosa/drug effects , Intestinal Mucosa/metabolism
15.
Phytochem Anal ; 2024 May 19.
Article in English | MEDLINE | ID: mdl-38764207

ABSTRACT

INTRODUCTION: Codonopsis Radix is a beneficial traditional Chinese medicine, and triterpenoid are the major bioactive constituents. Codonopsis pilosula var. modesta (Nannf.) L.T.Shen (CPM) is a precious variety of Codonopsis Radix, which is distributed at high mountain areas. The environment plays an important role in the synthesis and metabolism of active ingredients in medicinal plants, but there is no report elaborating on the effect of altitude on terpenoid metabolites accumulation in CPM. OBJECTIVES: This study aims to analyse the effects of altitude on triterpenoid biosynthetic pathways and secondary metabolite accumulation in CPM. MATERIAL AND METHODS: The untargeted metabolomics based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) and 10 triterpenoids based on ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) method were analysed at the low-altitude (1480 m) and high-altitude (2300 m) CPM fresh roots. The transcriptome based on high-throughput sequencing technology were combined to analyse the different altitude CPM triterpenoid biosynthetic pathways. RESULTS: A total of 17,351 differentially expressed genes (DEGs) and 55 differentially accumulated metabolites (DAMs) were detected from the different altitude CPM, and there are significant differences in the content of the 10 triterpenoids. The results of transcriptome study showed that CPM could significantly up-regulate the gene expression levels of seven key enzymes in the triterpenoid biosynthetic pathway. CONCLUSIONS: The CPM at high altitude is more likely to accumulate triterpenes than those at low altitude, which was related to the up-regulation of the gene expression levels of seven key enzymes. These results expand our understanding of how altitude affects plant metabolite biosynthesis.

16.
J Environ Manage ; 359: 121077, 2024 May.
Article in English | MEDLINE | ID: mdl-38718604

ABSTRACT

Tetrabromobisphenol A (TBBPA) and microplastics are emerging contaminants of widespread concern. However, little is known about the effects of combined exposure to TBBPA and microplastics on the physicochemical properties and microbial metabolism of anaerobic granular sludge. This study investigated the effects of TBBPA, polystyrene microplastics (PS MP) and polybutylene succinate microplastics (PBS MP) on the physicochemical properties, microbial communities and microbial metabolic levels of anaerobic granular sludge. The results showed that chemical oxygen demand (COD) removal of sludge was lowest in the presence of TBBPA alone and PS MP alone with 33.21% and 30.06%, respectively. The microorganisms promoted the secretion of humic substances under the influence of TBBPA, PS MP and PBS MP. The lowest proportion of genes controlling glycolytic metabolism in sludge was 1.52% when both TBBPA and PS MP were added. Microbial reactive oxygen species were increased in anaerobic granular sludge exposed to MPS. In addition, TBBPA treatment decreased electron transfer of the anaerobic granular sludge and disrupted the pathway of anaerobic microorganisms in acquiring adenosine triphosphate, and MPs attenuated the negative effects of TBBPA on the acetate methanogenesis process of the anaerobic granular sludge. This study provides a reference for evaluating the impact of multiple pollutants on anaerobic granular sludge.


Subject(s)
Microplastics , Polybrominated Biphenyls , Sewage , Polybrominated Biphenyls/toxicity , Polybrominated Biphenyls/metabolism , Microplastics/toxicity , Anaerobiosis , Reactive Oxygen Species/metabolism
17.
World J Gastrointest Oncol ; 16(5): 2091-2112, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38764846

ABSTRACT

BACKGROUND: For the first time, we investigated the oncological role of plexin domain-containing 1 (PLXDC1), also known as tumor endothelial marker 7 (TEM7), in hepatocellular carcinoma (HCC). AIM: To investigate the oncological profile of PLXDC1 in HCC. METHODS: Based on The Cancer Genome Atlas database, we analyzed the expression of PLXDC1 in HCC. Using immunohistochemistry, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blotting, we validated our results. The prognostic value of PLXDC1 in HCC was analyzed by assessing its correlation with clinicopathological features, such as patient survival, methylation level, tumor immune microenvironment features, and immune cell surface checkpoint expression. Finally, to assess the immune evasion potential of PLXDC1 in HCC, we used the tumor immune dysfunction and exclusion (TIDE) website and immunohistochemical staining assays. RESULTS: Based on immunohistochemistry, qRT-PCR, and Western blot assays, overexpression of PLXDC1 in HCC was associated with poor prognosis. Univariate and multivariate Cox analyses indicated that PLXDC1 might be an independent prognostic factor. In HCC patients with high methylation levels, the prognosis was worse than in patients with low methylation levels. Pathway enrichment analysis of HCC tissues indicated that genes upregulated in the high-PLXDC1 subgroup were enriched in mesenchymal and immune activation signaling, and TIDE assessment showed that the risk of immune evasion was significantly higher in the high-PLXDC1 subgroup compared to the low-PLXDC1 subgroup. The high-risk group had a significantly lower immune evasion rate as well as a poor prognosis, and PLXDC1-related risk scores were also associated with a poor prognosis. CONCLUSION: As a result of this study analyzing PLXDC1 from multiple biological perspectives, it was revealed that it is a biomarker of poor prognosis for HCC patients, and that it plays a role in determining immune evasion status.

18.
Chem Commun (Camb) ; 60(43): 5634-5637, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38716634

ABSTRACT

Rh-catalyzed three-component C(sp3)/C(sp2)-H activation has been achieved through a two-directing group strategy. This protocol provides a convenient and efficient pathway for the construction of diverse 8-alkyl quinoline derivatives in one-pot. Furthermore, mechanistic studies revealed that the first C-H amidation was significantly faster than the sequential C-H alkylation.

19.
New Phytol ; 2024 May 13.
Article in English | MEDLINE | ID: mdl-38741469

ABSTRACT

Ectomycorrhizal symbiosis, which involves mutually beneficial interactions between soil fungi and tree roots, is essential for promoting tree growth. To establish this symbiotic relationship, fungal symbionts must initiate and sustain mutualistic interactions with host plants while avoiding host defense responses. This study investigated the role of reactive oxygen species (ROS) generated by fungal NADPH oxidase (Nox) in the development of Laccaria bicolor/Populus tremula × alba symbiosis. Our findings revealed that L. bicolor LbNox expression was significantly higher in ectomycorrhizal roots than in free-living mycelia. RNAi was used to silence LbNox, which resulted in decreased ROS signaling, limited formation of the Hartig net, and a lower mycorrhizal formation rate. Using Y2H library screening, BiFC and Co-IP, we demonstrated an interaction between the mitogen-activated protein kinase LbSakA and LbNoxR. LbSakA-mediated phosphorylation of LbNoxR at T409, T477 and T480 positively modulates LbNox activity, ROS accumulation and upregulation of symbiosis-related genes involved in dampening host defense reactions. These results demonstrate that regulation of fungal ROS metabolism is critical for maintaining the mutualistic interaction between L. bicolor and P. tremula × alba. Our findings also highlight a novel and complex regulatory mechanism governing the development of symbiosis, involving both transcriptional and posttranslational regulation of gene networks.

20.
BMC Plant Biol ; 24(1): 457, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38797823

ABSTRACT

BACKGROUND: Cotton is globally important crop. Verticillium wilt (VW), caused by Verticillium dahliae, is the most destructive disease in cotton, reducing yield and fiber quality by over 50% of cotton acreage. Breeding resistant cotton cultivars has proven to be an efficient strategy for improving the resistance of cotton to V. dahliae. However, the lack of understanding of the genetic basis of VW resistance may hinder the progress in deploying elite cultivars with proven resistance. RESULTS: We planted the VW-resistant Gossypium hirsutum cultivar Zhongzhimian No.2 (ZZM2) in an artificial greenhouse and disease nursery. ZZM2 cotton was subsequently subjected to transcriptome sequencing after Vd991 inoculation (6, 12, 24, 48, and 72 h post-inoculation). Several differentially expressed genes (DEGs) were identified in response to V. dahliae infection, mainly involved in resistance processes, such as flavonoid and terpenoid quinone biosynthesis, plant hormone signaling, MAPK signaling, phenylpropanoid biosynthesis, and pyruvate metabolism. Compared to the susceptible cultivar Junmian No.1 (J1), oxidoreductase activity and reactive oxygen species (ROS) production were significantly increased in ZZM2. Furthermore, gene silencing of cytochrome c oxidase subunit 1 (COX1), which is involved in the oxidation-reduction process in ZZM2, compromised its resistance to V. dahliae, suggesting that COX1 contributes to VW resistance in ZZM2. CONCLUSIONS: Our data demonstrate that the G. hirsutum cultivar ZZM2 responds to V. dahliae inoculation through resistance-related processes, especially the oxidation-reduction process. This enhances our understanding of the mechanisms regulating the ZZM2 defense against VW.


Subject(s)
Disease Resistance , Gene Expression Profiling , Gene Regulatory Networks , Gossypium , Plant Diseases , Gossypium/genetics , Gossypium/microbiology , Gossypium/immunology , Plant Diseases/microbiology , Plant Diseases/genetics , Plant Diseases/immunology , Disease Resistance/genetics , Ascomycota/physiology , Gene Expression Regulation, Plant , Transcriptome , Verticillium
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