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2.
Cell Commun Signal ; 22(1): 234, 2024 Apr 20.
Article de Anglais | MEDLINE | ID: mdl-38643181

RÉSUMÉ

BACKGROUND: p66Shc, as a redox enzyme, regulates reactive oxygen species (ROS) production in mitochondria and autophagy. However, the mechanisms by which p66Shc affects autophagosome formation are not fully understood. METHODS: p66Shc expression and its location in the trophoblast cells were detected in vivo and in vitro. Small hairpin RNAs or CRISPR/Cas9, RNA sequencing, and confocal laser scanning microscope were used to clarify p66Shc's role in regulating autophagic flux and STING activation. In addition, p66Shc affects mitochondrial-associated endoplasmic reticulum membranes (MAMs) formation were observed by transmission electron microscopy (TEM). Mitochondrial function was evaluated by detected cytoplastic mitochondrial DNA (mtDNA) and mitochondrial membrane potential (MMP). RESULTS: High glucose induces the expression and mitochondrial translocation of p66Shc, which promotes MAMs formation and stimulates PINK1-PRKN-mediated mitophagy. Moreover, mitochondrial localized p66Shc reduces MMP and triggers cytosolic mtDNA release, thus activates cGAS/STING signaling and ultimately leads to enhanced autophagy and cellular senescence. Specially, we found p66Shc is required for the interaction between STING and LC3II, as well as between STING and ATG5, thereby regulates cGAS/STING-mediated autophagy. We also identified hundreds of genes associated several biological processes including aging are co-regulated by p66Shc and ATG5, deletion either of which results in diminished cellular senescence. CONCLUSION: p66Shc is not only implicated in the initiation of autophagy by promoting MAMs formation, but also helps stabilizing active autophagic flux by activating cGAS/STING pathway in trophoblast.


Sujet(s)
Autophagosomes , , Protéine transformante-1 contenant un domaine d'homologie-2 de Src/métabolisme , Autophagosomes/métabolisme , Autophagie , ADN mitochondrial/métabolisme , Trophoblastes/métabolisme , Glucose/métabolisme , Nucleotidyltransferases/métabolisme
3.
Aging (Albany NY) ; 16(8): 7293-7310, 2024 04 23.
Article de Anglais | MEDLINE | ID: mdl-38656879

RÉSUMÉ

BACKGROUND: CESC is the second most commonly diagnosed gynecological malignancy. Given the pivotal involvement of metabolism-related genes (MRGs) in the etiology of multiple tumors, our investigation aims to devise a prognostic risk signature rooted in cancer stemness and metabolism. METHODS: The stemness index based on mRNA expression (mRNAsi) of samples from the TCGA dataset was computed using the One-class logistic regression (OCLR) algorithm. Furthermore, potential metabolism-related genes related to mRNAsi were identified through weighted gene co-expression network analysis (WGCNA). We construct a stemness-related metabolic gene signature through shrinkage estimation and univariate analysis, thereby calculating the corresponding risk scores. Moreover, we selected corresponding DEGs between groups with high- and low-risk score and conducted routine bioinformatic analyses. Furthermore, we validated the expression of four hub genes at the protein level through immunohistochemistry (IHC) in samples obtained from our patient cohort. RESULTS: According to the findings, it was found that six genes-AKR1B10, GNA15, ALDH1B1, PLOD2, LPCAT1, and GPX8- were differentially expressed in both TCGA-CSEC and GEO datasets among 23 differentially expressed metabolism-related genes (DEMRGs). mRNAsi exhibited a notable association with the extent of key oncogene mutation. The results showed that the AUC values for forecasting survival at 1, 3, and 5 years are 0.715, 0.689, and 0.748, individually. We observed a notable association between the risk score and different immune cell populations, along with enrichment in crucial signaling pathways in CESC. Four genes differentially expressed between different risk score groups were validated by IHC to be highly expressed in the CESC samples at the protein level. CONCLUSION: The current investigation indicated that a 3-gene signature based on stemness-related metabolic and 4 hub genes with differential expression between high and low-risk score subgroups may serve as valuable prognostic markers and potential therapeutic targets in CESC.


Sujet(s)
Régulation de l'expression des gènes tumoraux , Cellules souches tumorales , Tumeurs du col de l'utérus , Humains , Femelle , Pronostic , Tumeurs du col de l'utérus/génétique , Tumeurs du col de l'utérus/anatomopathologie , Tumeurs du col de l'utérus/mortalité , Tumeurs du col de l'utérus/métabolisme , Cellules souches tumorales/métabolisme , Cellules souches tumorales/anatomopathologie , Carcinome épidermoïde/génétique , Carcinome épidermoïde/anatomopathologie , Carcinome épidermoïde/métabolisme , Carcinome épidermoïde/mortalité , Adénocarcinome/génétique , Adénocarcinome/anatomopathologie , Adénocarcinome/mortalité , Adénocarcinome/métabolisme , Marqueurs biologiques tumoraux/génétique , Marqueurs biologiques tumoraux/métabolisme , Analyse de profil d'expression de gènes , Adulte d'âge moyen , Transcriptome
4.
Exp Ther Med ; 27(1): 8, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-38223326

RÉSUMÉ

Butorphanol is a synthetic selective opioid receptor antagonist that exhibits substantial analgesic effects. The present study aimed to explore the effects of butorphanol on a neurodegenerative disease cell model and to investigate its specific regulatory mechanism. Cell viability of PC12 cells was assessed using the Cell Counting Kit-8 assay. Oxidative stress levels were measured by the corresponding kits and western blotting of specific protein markers. Apoptosis was determined using the terminal-deoxynucleoitidyl transferase mediated nick end labeling assay and by western blotting. Western blotting was used to analyze the expression levels of c-Jun NH2-terminal kinase (JNK)/p38 signaling pathway-related proteins. Thiobarbituric acid-reactive substances and Fe+2 content were detected using the corresponding assay kits and the expression levels of ferroptosis-associated proteins were assessed by western blotting following the addition of the JNK activator anisomycin (ANI). Oxidative stress and apoptosis were examined with the aforementioned assays following the supplementation of ANI or the ferroptosis inducer erastin (ERA). It was revealed that butorphanol dose-dependently enhanced the viability and suppressed the oxidative stress and apoptosis of H2O2-treated PC12 cells. In addition, butorphanol blocked JNK/p38 signaling and hampered ferroptosis, while this effect was reversed by ANI. ANI or ERA reversed the effects of butorphanol on oxidative stress and apoptosis of H2O2-treated PC12 cells. In summary, butorphanol suppressed ferroptosis by blocking JNK/p38 signaling to impart inhibitory effects on oxidative stress and apoptosis in a neurodegenerative disease cell model.

5.
Br J Haematol ; 204(4): 1207-1218, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-37967471

RÉSUMÉ

The coronavirus disease 2019 (COVID-19) pandemic has a significant impact on the immune system. This is the first and largest study on pre-existing immune thrombocytopenia (ITP) patients infected with COVID-19 in China. We prospectively collected ITP patients infected with COVID-19 enrolled in the National Longitudinal Cohort of Hematological Diseases (NICHE, NCT04645199) and followed up for at least 1 month after infection. One thousand and one hundred forty-eight pre-existing ITP patients were included. Two hundred and twelve (18.5%) patients showed a decrease in the platelet (PLT) count after infection. Forty-seven (4.1%) patients were diagnosed with pneumonia. Risk factors for a decrease in the PLT count included baseline PLT count <50 × 109/L (OR, 1.76; 95% CI, 1.25-2.46; p = 0.001), maintenance therapy including thrombopoietin receptor agonists (TPO-RAs) (OR, 2.27; 95% CI, 1.60-3.21; p < 0.001) and previous splenectomy (OR, 1.98; 95% CI, 1.09-3.61; p = 0.03). Risk factors for pneumonia included age ≥40 years (OR, 2.45; 95% CI, 1.12-5.33; p = 0.02), ≥2 comorbidities (OR, 3.47; 95% CI, 1.63-7.64; p = 0.001), maintenance therapy including TPO-RAs (OR, 2.14; 95% CI, 1.17-3.91; p = 0.01) and immunosuppressants (OR, 3.05; 95% CI, 1.17-7.91; p = 0.02). In this cohort study, we described the characteristics of pre-existing ITP patients infected with COVID-19 and identified several factors associated with poor outcomes.


Sujet(s)
COVID-19 , Purpura thrombopénique idiopathique , Thrombopénie , Humains , Adulte , Purpura thrombopénique idiopathique/épidémiologie , Purpura thrombopénique idiopathique/thérapie , Études de cohortes , Études prospectives , Thrombopénie/épidémiologie , Thrombopénie/étiologie , Thrombopoïétine , Protéines de fusion recombinantes , Récepteur Fc , Hydrazines
6.
Huan Jing Ke Xue ; 44(4): 2083-2092, 2023 Apr 08.
Article de Chinois | MEDLINE | ID: mdl-37040958

RÉSUMÉ

Environmental heterogeneity can not only increase species diversity to some extent but also affect the stability of terrestrial communities. However, how environmental heterogeneity affects species diversity of epilithic diatom communities in aquatic ecosystems is rarely reported. In this study, therefore, epilithic diatoms and their roles in driving species diversity were explored by quantifying and comparing the environmental heterogeneity in Xiangxi River, a tributary of the Three Gorges Reservoir Area (TGR), on a time scale. The results showed that environmental heterogeneity, taxonomic ß-diversity, and functional ß-diversity in non-impoundment periods were significantly higher than those in impoundment periods. Moreover, the turnover components in the two hydrological periods showed the highest contribution to ß-diversity. However, the taxonomic α-diversity in impoundment periods was significantly higher than that in non-impoundment periods. In addition, functional richness in functional α-diversity was significantly higher in non-impoundment periods than that in impoundment periods, whereas there was no significant difference in other functional α-diversity, i.e., functional dispersion and functional evenness, found between the two periods. Multiple regression on (dis)similarity matrices (MRM) analysis indicated that ammonium nitrogen (NH4+-N) and silicate (SiO32--Si) were the key environmental heterogeneous factors affecting the epilithic diatom community in Xiangxi River during the non-impoundment periods, whereas the key heterogeneous factors were ammonium nitrogen (NH4+-N), silicate (SiO32--Si), and total phosphorus (TP) during the impoundment periods. These results suggested that the environmental heterogeneity during different hydrological periods in TGR can significantly affect the community structure of epilithic diatoms, resulting in the differentiation of species within the community and even affecting the stability of aquatic ecosystems.


Sujet(s)
Diatomées , Rivières , Écosystème , Surveillance de l'environnement/méthodes , Azote/analyse
7.
Huan Jing Ke Xue ; 44(2): 857-867, 2023 Feb 08.
Article de Chinois | MEDLINE | ID: mdl-36775609

RÉSUMÉ

In order to investigate the relationship between phytoplankton community functional group compositions and resource use efficiency in important tributaries of the Three Gorges Reservoir, phytoplankton and environment parameters were sampled from five tributaries, the Xiangxi River, Daning River, Meixi River, Pengxi River, and Huangjin River, in August and November, 2020. There were 119 species (variants) belonging to 62 genera and 7 phyla identified in summer, whereas 118 species (variants) belonging to 7 divisions of 58 genera were found in winter. According to Padisak's theory, all phytoplankton were divided into 25 functional groups, of which there were six important functional groups in both summer and winter:L0, H1, D, Y, MP, and P in summer and L0, H1, A, M, MP, and Y in winter. The α-diversity of the phytoplankton functional group in summer was higher than that in winter. Moreover, a higher α-diversity was also found in downstream samples relative to that in upstream samples, indicating that the community structure was more complex, and the community stability was relatively better in downstream regions of the rivers. Redundancy analysis (RDA) showed that the environment factors, i.e., ν, pH, permanganate index, WT, and RUETN, significantly affected phytoplankton functional groups (P<0.05). Variance partitioning analysis (VPA) indicated that environmental factors had a higher explanatory degree for the change in functional group composition in summer (45.23%); on the contrary, resource use efficiency had a higher explanatory degree in winter (42.33%). The linear fitted model showed that functional groups L0, H1, D, and Y showed a significant positive correlation relationship with RUETN and RUETP in summer, whereas only four functional groups (M, MP, Y, and A) had a linear relationship with RUETP, and all function groups had a good linear relationship with RUETN in winter. These results indicated that the functional groups belonging to cyanobacteria, dinoflagellates, and cryptophyta were more efficient at using limited resources in summer, whereas the diatoms had a good linear relationship with resource use efficiency and formed a dominant group in the low temperature environment of winter. These results suggest that the impounding of the Three Gorges Reservoir area can significantly change the resource use efficiency of phytoplankton, resulting in changes in the phytoplankton functional group composition and community structure.


Sujet(s)
Cyanobactéries , Diatomées , Phytoplancton , Surveillance de l'environnement/méthodes , Phosphore/analyse , Saisons , Chine
8.
Brain Behav Immun ; 107: 76-86, 2023 01.
Article de Anglais | MEDLINE | ID: mdl-36198341

RÉSUMÉ

Current treatments for chronic pain are unsatisfactory, therefore, new therapeutics are urgently needed. Our previous study indicated that KATP channel openers have analgesic effects, but the underlying mechanism has not been elucidated. We speculated that KATP channel openers might increase suppressor of cytokine signaling (SOCS)-3 expression to induce inflammatory tolerance and attenuate chronic pain. Postoperative pain was induced by plantar incision to establish a chronic pain model. Growth arrest-specific 6 (Gas6)-/- and Axl-/- mice were used for signaling studies. The microglia cell line BV-2 was cultured for the in vitro experiments. The KATP channel opener significantly attenuated incision-induced mechanical allodynia in mice associated with the upregulated expression of SOCS3. Opening KATP channels induced the expression of SOCS3 in the Gas6/Axl signaling pathway in microglia, inhibited incision-induced mechanical allodynia by activating the Gas6/Axl-SOCS3 signaling pathway, and induced inflammatory tolerance to relieve neuroinflammation and postoperative pain. We demonstrated that opening of the KATP channel opening activated Gas6/Axl/SOCS3 signaling to induce inflammatory tolerance and relieve chronic pain. We explored a new target for anti-inflammatory and analgesic effects by regulating the innate immune system and provided a theoretical basis for clinical preemptive analgesia.


Sujet(s)
Douleur chronique , Animaux , Souris , Douleur chronique/prévention et contrôle , Douleur postopératoire , Adénosine triphosphate
9.
Huan Jing Ke Xue ; 43(10): 4480-4488, 2022 Oct 08.
Article de Chinois | MEDLINE | ID: mdl-36224134

RÉSUMÉ

The succession of dominant species always occurs during cyanobacterial blooms because there are certain conditions for cyanobacterial blooms formed by different cyanobacteria; this results in more uncertain and complex effects in cyanobacterial blooms. However, the succession pattern and consequences of dominant species and its driving factors have not received enough attention during cyanobacteria blooms. In this study, the phytoplankton community characteristics and water environment factors of Nanpeng Reservoir, a drinking water source in Chongqing, were monitored and analyzed from April to September 2018. The results showed that:① a total of 108 species of phytoplankton belonging to 59 genera and 8 phyla were identified in Nanpeng Reservoir. Of this, 13 species of 4 phyla were identified as dominant species, among which the dominance index of Cylindrospermopsis raciborskii was the highest, followed by that of Pseudoanabaena sp. ② The most dominant cyanobacteria were Pseudoanabaena and Cylindrospermopsis in May and July, respectively, in which cyanobacteria density peaked, whereas the Shannon-Weiner diversity and Pielou evenness were significantly lower than those in the other months. ③ NMDS results showed that the correlation between Cylindrospermopsis or Pseudoanabaena and the ambient phytoplankton community was 0.58 and 0.48, respectively. Moreover, the VPA results showed that 47.51% of the community variation could be explained by environmental factors, and only 12.04% and 12.74% of variation in community composition could be explained by Cylindrospermopsis and Pseudoanabaena, respectively. ④ The abundance of Cylindrospermopsis was significantly positively affected by WT, pH, and RUEN and negatively affected by SD and RUEP. However, the abundance of Pseudoanabaena was significantly positively affected by permanganate index and negatively affected by EC and DO. These results suggested that both dominating cyanobacteria had significant effects on the surrounding phytoplankton community. Relative to that of Pseudoanabaena, however, Cylindrospermopsis had a more obvious impact on the aquatic ecosystem. Moreover, the synergistic effect of N limitation and warming of the water column may have caused the replacement of Pseudoanabaena with Cylindrospermopsis to form a dominant population.


Sujet(s)
Cyanobactéries , Eau de boisson , Écosystème , Eutrophisation , Phytoplancton
10.
Microbiol Res ; 262: 127098, 2022 Sep.
Article de Anglais | MEDLINE | ID: mdl-35753182

RÉSUMÉ

To elucidate the interspecies connectivity between cyanobacteria and other bacteria (noncyanobacteria), microbial diversity and composition were investigated through high-throughput sequencing (HTS) in a drinking water reservoir in Chongqing city, Southwest China, during Raphidiopsis raciborskii blooms. Significant temporal changes were observed in microbial community composition during the sampling period, primarily reflected by variations in relative bacterial abundance. The modularity analysis of the network demonstrated that the bacterial community forms co-occurrence/exclusion patterns in response to variations in environmental factors. Moreover, five modules involved in the dynamic phases of the R. raciborskii bloom were categorized into the Pre-Bloom, Bloom, Post-Bloom, and Non-Bloom Groups. The reservoir was eutrophic (i.e., the average concentrations of total nitrogen (TN) and total phosphorus (TP) were 2.32 and 0.07 mg L-1, respectively) during the investigation; however, Pearson's correlation coefficient showed that R. raciborskii was not significantly correlated with nitrogen and phosphorus. However, other environmental factors, such as water temperature, pH, and the permanganate index, were positively correlated with R. raciborskii. Importantly, Proteobacteria (α-, γ-Proteobacteria), Acidobacteria, Chloroflexi, and Firmicutes were preferentially associated with increased R. raciborskii blooms. These results suggested that the transition of R. raciborskii bloom-related microbial modules and their keystone species could be crucial in the development and collapse of R. raciborskii blooms and could provide a fundamental basis for understanding the linkage between the structure and function of the microbial community during bloom dynamics.


Sujet(s)
Cylindrospermopsis , Eau de boisson , Azote , Phosphore
11.
Mol Cell Endocrinol ; 547: 111598, 2022 05 01.
Article de Anglais | MEDLINE | ID: mdl-35157929

RÉSUMÉ

Maternal pregnancy hyperglycemia is often accompanied by placental dysfunction. During placental development, epithelial-mesenchymal transition (EMT) contributes to the transformation of relatively noninvasive trophoblasts into highly invasive extravillous trophoblasts (EVTs). However, the specific role of EMT in placentas under hyperglycemia environments remains relatively unexplored. Stanniocalcin2 (STC2) regulates EMT in many cancers. In this study, we first demonstrated that STC2 expression was upregulated in GDM placenta. We found that STC2 activated autophagy and suppressed EMT in high-glucose-treated EVTs and was associated with a lack of invasiveness. Specifically, STC2 inhibited the interactions between p62/SQSTM1 (p62) and EMT transcription factors to promote the degradation of Twist1 and Snail via a proteasome-dependent pathway. Furthermore, the PI3K/AKT/AMPK signaling pathway was involved in the regulation of autophagy and EMT by STC2. Taken together, our results reveal that STC2 may serve as a potential prognostic biomarker in GDM and sheds light on the regulatory mechanisms of trophoblast invasion.


Sujet(s)
Transition épithélio-mésenchymateuse , Glycoprotéines , Protéines et peptides de signalisation intercellulaire , Trophoblastes , Autophagie , Mouvement cellulaire , Femelle , Glucose/génétique , Glucose/pharmacologie , Humains , Phosphatidylinositol 3-kinases/métabolisme , Placenta/métabolisme , Grossesse , Trophoblastes/métabolisme
12.
Harmful Algae ; 111: 102150, 2022 01.
Article de Anglais | MEDLINE | ID: mdl-35016763

RÉSUMÉ

Phosphorus (P) is a vital macronutrient associated with the growth and proliferation of Raphidiopsis raciborskii, an invasive and notorious bloom-forming cyanobacterium. However, the molecular mechanisms involved in P acclimation remain largely unexplored for Raphidiopsis raciborskii. Here, transcriptome sequencing of Raphidiopsis raciborskii was conducted to reveal multifaceted mechanisms involved in mimicking dipotassium phosphate (DIP), ß-glycerol phosphate (Gly), 2-aminoethylphosphonic acid (AEP), and P-free conditions (NP). Chlorophyll a fluorescence parameters showed significant differences in the NP and AEP groups compared with the DIP and Gly-groups. Expression levels of genes related to phosphate transportation and uptake, organic P utilization, nitrogen metabolism, urea cycling, carbon fixation, amino acid metabolism, environmental information, the ATP-synthesis process in glycolysis, the tricarboxylic acid (TCA) cycle, and the pentose phosphate pathway were remarkably upregulated, while those related to photosynthesis, phycobiliproteins, respiration, oxidative phosphorylation, sulfur metabolism, and genetic information were markedly downregulated in the NP group relative to the DIP group. However, the expression of genes involved in organic P utilization, the urea cycle, and genetic information in the Gly-group, and carbon-phosphorus lyase, genetic information and environmental information in the AEP group were significantly increased compared to the DIP group. Together, these results indicate that Raphidiopsis raciborskii exhibits the evolution of coordination of multiple metabolic pathways and certain key genes to adapt to ambient P changes, which implies that if P is reduced to control Raphidiopsis raciborskii bloom, there is a risk that external nutrients (such as nitrogen, amino acids, and urea) will stimulate the growth or metabolism of Raphidiopsis.


Sujet(s)
Phosphore , Transcriptome , Chlorophylle A , Cylindrospermopsis , Nutriments
13.
J Neuroinflammation ; 19(1): 25, 2022 Jan 29.
Article de Anglais | MEDLINE | ID: mdl-35093117

RÉSUMÉ

BACKGROUND: The development of morphine tolerance is a clinical challenge for managing severe pain. Studies have shown that neuroinflammation is a critical aspect for the development of analgesic tolerance. We found that AMPK-autophagy activation could suppress neuroinflammation and improve morphine tolerance via the upregulation of suppressor of cytokine signaling 3 (SOCS3) by inhibiting the processing and maturation of microRNA-30a-5p. METHODS: CD-1 mice were utilized for the tail-flick test to evaluate morphine tolerance. The microglial cell line BV-2 was utilized to investigate the mechanism of AMPK-autophagy-mediated posttranscriptional regulation of SOCS3. Proinflammatory cytokines were measured by western blotting and real-time PCR. The levels of SOCS3 and miRNA-processing enzymes were evaluated by western blotting, real-time PCR and immunofluorescence staining. RESULTS: Based on experimental verification, miRNA-30a-5p could negatively regulate SOCS3. The AMPK activators AICAR, resveratrol and metformin downregulated miRNA-30a-5p. We found that AMPK activators specifically inhibited the processing and maturation of miRNA-30a-5p in microglia by degrading DICER and AGO2 via autophagy. Furthermore, a miRNA-30a-5p inhibitor significantly improved morphine tolerance via upregulation of SCOS3 in mice. It markedly increased the level of SOCS3 in the spinal cord of mice and subsequently inhibited morphine-induced phosphorylation of NF-κB p65. In addition, a miRNA-30a-5p inhibitor decreased the levels of IL-1ß and TNF-α caused by morphine in microglia. CONCLUSION: AMPK-autophagy activation suppresses neuroinflammation and improves morphine tolerance via the upregulation of SOCS3 by inhibiting miRNA-30a-5p.


Sujet(s)
microARN , Morphine , AMP-Activated Protein Kinases/métabolisme , Autophagie , Humains , microARN/métabolisme , Morphine/pharmacologie , Maladies neuro-inflammatoires , Protéine-3 suppressive de la signalisation des cytokine/génétique , Protéine-3 suppressive de la signalisation des cytokine/métabolisme
14.
Appl Microbiol Biotechnol ; 105(23): 8761-8769, 2021 Dec.
Article de Anglais | MEDLINE | ID: mdl-34748038

RÉSUMÉ

Promoters play an important role in regulating gene expression, and construction of microbial cell factories requires multiple promoters for balancing the metabolic pathways. However, there are only a limited number of characterized promoters for gene expression in the methylotrophic yeast Ogataea polymorpha, which hampers the extensive harnessing of this important yeast toward a cell factory. Here we characterized the promoters of methanol utilization pathway, precursor supply pathway, and reactive oxygen species (ROS) defense system, by using a green fluorescence protein variant (GFPUV) as a quantification signal. Finally, the characterized promoters were used for tuning a fatty alcohol biosynthetic pathway in O. polymorpha and realized fatty alcohol production from methanol. This promoter box should be helpful for gene expression and pathway optimization in the methylotrophic yeast O. polymorpha. KEY POINTS : • 22 promoters related to methanol metabolism were characterized in O. polymorpha. • Promoter truncation resulted shorter and compact promoters. • Promoters with various strengths were used for regulating a fatty alcohol biosynthesis from methanol.


Sujet(s)
Génie métabolique , Méthanol , Pichia/génétique , Régions promotrices (génétique) , Saccharomycetales
15.
Huan Jing Ke Xue ; 42(7): 3242-3252, 2021 Jul 08.
Article de Chinois | MEDLINE | ID: mdl-34212650

RÉSUMÉ

Changes in the community stability of freshwater phytoplankton not only induce a series of ecological environment problems but also influence freshwater ecosystem service functions. To understand the changes in community stability and its driving factors, phytoplankton and environmental parameters were analyzed at 11 sample sites in Huaxi River, a tributary of the Three Gorges Reservoir, in spring, summer, autumn, and winter. Moreover, the resource use efficiency (RUEPP), phytoplankton richness (S), phytoplankton evenness (J), and community turnover (BC) were also determined. Results showed that a total of 8 phyla, including 103 genera and 380 species, were identified in Huaxi River throughout the year. Among them, 264 species were collected in spring, 181 in summer, 197 in autumn, and 183 in winter. The number of Chlorophyta was the largest, followed by Bacillariophyta, Euglenophyta, and Cyanophyta. The number of species and cell density in S0 site were the smallest, while those in S2 site were the largest. The RUEPP was fluctuated in four seasons, with the maximum in summer and the minimum in autumn. BC was significantly negatively correlated with RUEPP, phytoplankton richness, total phosphorus (TP), orthophosphate (PO43--P), total nitrogen (TN), nitrate (NO3--N), permanganate index, and conductivity (Spc); however, it was significantly positively correlated with phytoplankton evenness and dissolved oxygen (DO). These results suggest that water level regulation in the Three Gorges Reservoir has a significant impact on the structure of phytoplankton community in Huaxi River, which leads to the instability of phytoplankton community and easy replacement, and the degree of community turnover is affected by the combined effect of biological and abiotic factors.


Sujet(s)
Diatomées , Phytoplancton , Chine , Écosystème , Surveillance de l'environnement , Azote/analyse , Phosphore/analyse , Rivières , Saisons
16.
Article de Anglais | MEDLINE | ID: mdl-33042863

RÉSUMÉ

Studies have shown that exposure to environmental tobacco smoke can increase the risk of bacterial meningitis, and nicotine is the core component of environmental tobacco smoke. Autophagy is an important way for host cells to eliminate invasive pathogens and resist infection. Escherichia coli K1 strain (E. coli K1) is the most common Gram-negative bacterial pathogen that causes neonatal meningitis. The mechanism of nicotine promoting E. coli K1 to invade human brain microvascular endothelial cells (HBMECs), the main component of the blood-brain barrier, is not clear yet. Our study found that the increase of HBMEC autophagy level during E. coli K1 infection could decrease the survival of intracellular bacteria, while nicotine exposure could inhibit the HBMEC autophagic response of E. coli K1 infection by activating the NF-kappa B and PI3K/Akt/mTOR pathway. We concluded that nicotine could inhibit HBMEC autophagy upon E. coli K1 infection and decrease the scavenging effect on E. coli K1, thus promoting the occurrence and development of neonatal meningitis.


Sujet(s)
Escherichia coli , Nicotine , Autophagie , Encéphale/métabolisme , Cellules cultivées , Cellules endothéliales/métabolisme , Escherichia coli/métabolisme , Humains , Nouveau-né , Nicotine/pharmacologie , Phosphatidylinositol 3-kinases/métabolisme
17.
Cancer Lett ; 492: 162-173, 2020 11 01.
Article de Anglais | MEDLINE | ID: mdl-32858102

RÉSUMÉ

Estrogen receptor α (ER) acts as an oncogenic signal in endometrial endometrioid carcinoma. ER binding activity largely depends on chromatin remodeling and recruitment of transcription factors to estrogen response elements. A deeper understanding of these regulatory mechanisms may uncover therapeutic targets for ER-dependent endometrial cancers. We show that estrogen induces accessible chromatin and ER binding at a subset of enhancers, which form higher-order super enhancers that are vital for ER signaling. ER positively correlates with active enhancers in primary tumors, and tumors were effectively classified into molecular subtypes with chromatin accessibility dynamics and ER-dependent gene signature. ARID1A binds within ER-bound enhancers and regulates ER-dependent transcription. Knockdown of ARID1A or fulvestrant treatment profoundly affects the gene-expression program, and inhibits cell growth phenotype by affecting the chromatin environment. Importantly, we found dysregulated expression of circadian rhythms genes by estrogen in cancer cells and in primary tumors. Knockdown of ARID1A reduces the chromatin accessibility and ER binding at enhancers of the circadian gene ARNTL and BHLHE41, leading to a decreased expression of these genes. Altogether, we uncover a critical role for ARID1A in ER signaling and therapeutic target in ER-positive endometrial cancer.


Sujet(s)
Facteurs de transcription ARNTL/génétique , Facteurs de transcription à motif basique hélice-boucle-hélice/génétique , Chromatine/métabolisme , Protéines de liaison à l'ADN/physiologie , Tumeurs de l'endomètre/métabolisme , Régulation de l'expression des gènes tumoraux , Récepteurs des oestrogènes/physiologie , Facteurs de transcription/physiologie , Femelle , Humains , Protéines du muscle/physiologie , Transduction du signal/physiologie , Facteurs de transcription à domaine TEA
18.
Mol Cell Endocrinol ; 502: 110674, 2020 02 15.
Article de Anglais | MEDLINE | ID: mdl-31811899

RÉSUMÉ

Autophagy plays an essential role in gestational diabetes mellitus (GDM). Death-associated protein kinase-3 (DAPK3) regulates a variety of cellular functions; however, the relationship between DAPK3 and autophagy is unknown. In this study, we aim to investigate whether DAPK3 is associated with autophagy in GDM, and we found that DAPK3 was upregulated in the placenta of GDM patients and extravillous trophoblast cells under high-glucose conditions. Silencing DAPK3 decreased the assembly of the STX17-SNAP29-VAMP8 complex, leading to the blockade of autophagosome-lysosome fusion by mediating synaptosomal-associated protein 29 (SNAP29). Moreover, knockdown of DAPK3 ameliorates cell invasion and mediates autophagy in high glucose, and does not alter the expression of autophagy-related genes in normal glucose. Our study demonstrates the significance of DAPK3 in autophagy and GDM, which may provide new insights into the molecular mechanisms regulating trophoblast invasion.


Sujet(s)
Autophagosomes/métabolisme , Death-associated protein kinases/génétique , Diabète gestationnel/génétique , Lysosomes/métabolisme , Protéines Qb-SNARE/métabolisme , Protéines Qc-SNARE/métabolisme , Lignée cellulaire , Mouvement cellulaire , Death-associated protein kinases/métabolisme , Diabète gestationnel/métabolisme , Femelle , Techniques de knock-down de gènes , Glucose/effets indésirables , Humains , Grossesse , Trophoblastes/cytologie , Trophoblastes/effets des médicaments et des substances chimiques , Trophoblastes/métabolisme , Régulation positive
19.
J Infect Dis ; 219(3): 470-479, 2019 01 09.
Article de Anglais | MEDLINE | ID: mdl-30202861

RÉSUMÉ

FimH-mediated bacterial invasion and polymorphonuclear neutrophil (PMN) transmigration across human brain microvascular endothelial cells (HBMECs) are required for the pathogenesis of Escherichia coli meningitis. However, the underlying mechanism remains unclear. This study demonstrated that the TnphoA mutant (22A33) and FimH-knockout mutant (ΔFimH) of E coli strain E44, which resulted in inactivation of FimH, were less invasive and less effective in promoting PMN transmigration than their wild-type strain. FimH protein induced PMN transmigration, whereas calmodulin inhibitor significantly blocked this effect. Moreover, immunofluorescence and co-immunoprecipitation analysis indicated that colocalized CD48 and α7 nAChR formed a complex on the surface of HBMECs that is associated with increased cofilin dephosphorylation, which could be remarkably enhanced by FimH+ E44. Our study concluded that FimH-induced E coli K1 invasion and PMN migration across HBMECs may be mediated by the CD48-α7nAChR complex in lipid rafts of HBMEC via Ca2+ signaling and cofilin dephosphorylation.


Sujet(s)
Adhésines d'Escherichia coli/métabolisme , Encéphale/microbiologie , Antigène CD48/métabolisme , Cellules endothéliales/métabolisme , Cellules endothéliales/microbiologie , Escherichia coli/métabolisme , Protéines de fimbriae/métabolisme , Granulocytes neutrophiles/microbiologie , Récepteur nicotinique de l'acétylcholine alpha7/métabolisme , Adhésines d'Escherichia coli/génétique , Calcium/métabolisme , Mouvement cellulaire , Escherichia coli/pathogénicité , Protéines de fimbriae/génétique , Techniques de knock-down de gènes , Humains , Microdomaines membranaires , Méningite à Escherichia coli/microbiologie , Méningite à Escherichia coli/anatomopathologie , Transduction du signal , Facteurs de virulence/génétique , Facteurs de virulence/métabolisme
20.
Endocrinology ; 158(8): 2522-2532, 2017 08 01.
Article de Anglais | MEDLINE | ID: mdl-28838138

RÉSUMÉ

Autophagy is a dynamic process that degrades and recycles cellular organelles and proteins to maintain cell homeostasis. Alterations in autophagy occur in various diseases; however, the role of autophagy in gestational diabetes mellitus (GDM) is unknown. In the present study, we characterized the roles and functions of autophagy in GDM patient samples and extravillous trophoblasts cultured with glucose. We found significantly enhanced autophagy in GDM patients. Moreover, high glucose levels enhanced autophagy and cell apoptosis, reducing proliferation and invasion, and these effects were ameliorated through knockdown of ATG5. Genome-wide 5-hydroxymethylcytosine data analysis further revealed the epigenomic regulatory circuitry underlying the induced autophagy and apoptosis in GDM and preeclampsia. Finally, RNA sequencing was performed to identify gene expression changes and critical signaling pathways after silencing of ATG5. Our study has demonstrated the substantial functions of autophagy in GDM and provides potential therapeutic targets for the treatment of GDM patients.


Sujet(s)
Autophagie/physiologie , Diabète gestationnel/physiopathologie , Placenta/cytologie , Adulte , Apoptose/physiologie , Glycémie , Lignée cellulaire , Épigénomique , Femelle , Régulation de l'expression des gènes , Humains , Hyperglycémie , Grossesse
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