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1.
mBio ; : e0243024, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39365062

RESUMEN

Gene expression and proper downstream cellular functions upon facing environmental shifts depend on the combined and cooperative regulation of genetic networks. Here, we identified cAMP receptor protein (CRP) as a master regulator of (p)ppGpp (guanosine tetra- and penta-phosphate) homeostasis. Via CRP-mediated direct transcriptional regulation of the (p)ppGpp synthetase/hydrolase RelA and SpoT, cAMP-CRP stimulates pervasive accumulation of (p)ppGpp under glucose-limiting conditions. Notably, CRP exerts a nonclassical property as a translational regulator through YfiQ-dependent acetylation of ribosome protein S1 at K247, which further enhances the translation of RelA, SpoT, and CRP itself. From a synthetic biology perspective, this self-activating feedback loop for (p)ppGpp synthesis highlights the function of CRP-mediated dual enhancement (CMDE) in controlling bacterial gene expression, which enables stable activation of genetic circuits. CMDE applied in synthetic circuits leads to a stable increase in p-coumaric acid, cinnamic acid, and pinosylvin production. Our findings showed that CRP-mediated dual circuits for (p)ppGpp regulation enable robust activation that could address bioproduction and other biotechnological needs.IMPORTANCETranscriptional-translational coordination is fundamental for rapid and efficient gene expression in most bacteria. Here, we uncovered the roles of cAMP-CRP in this process. We found that CRP distinctly increases RelA and SpoT transcription and translation, and that acetylation of S1 at K247 accelerates the self-activation of the leading CRP under glucose-limiting conditions. We further found that elevated (p)ppGpp significantly impedes the formation of the cAMP-CRP complex, an active form responsible for transcriptional activation. A model was created in which cAMP-CRP and (p)ppGpp cooperate to dynamically modulate the efficiency of transcriptional-translational coordination responses to stress. More broadly, productive activation in synthetic circuits was achieved through the application of CRP-mediated dual enhancement (CMDE), promising to inspire new approaches for the development of cell-based biotechnologies.

3.
Cell Signal ; 124: 111477, 2024 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-39426495

RESUMEN

Aberrant glycosylation, resulting from dysregulated expression of glycosyltransferases, is a prevalent feature of cancer cells. N-acetylgalactosaminyltransferase-14 (GALNT14) serves as a pivotal enzyme responsible for initiating O-GalNAcylation. It remains unclear whether and how GALNT14 affects lung adenocarcinoma (LUAD). Here, GALNT14 expression in LUAD was analyzed by searching public databases and verified by examining clinical samples. Bioinformatics, LC-MS/MS, RNA-seq, and RIP-seq analyses were used to uncover the mechanism underlying GALNT14. We observed that GALNT14 was frequently overexpressed in LUAD tissues. High GALNT14 expression was positively associated with advanced TNM stage, larger tumor size, and unfavorable prognosis. Functionally, GALNT14 facilitated LUAD cell proliferation, migration, and invasion in vitro and accelerated tumor growth in vivo. Mechanistically, GALNT14 reduced the accumulation of endogenous reactive oxygen species (ROS) to exert its oncogenic function via O-glycosylating hnRNPUL1 to upregulate AKR1C2 expression. Meanwhile, GALNT14 expression was directly modulated by miR-125a.These findings indicated that GALNT14-mediated O-GalNAcylation could drive LUAD progression via eliminating ROS and might be a valuable therapeutic target.

4.
World J Gastrointest Surg ; 16(9): 2996-3007, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39351573

RESUMEN

BACKGROUND: The transjugular intrahepatic portosystemic shunt (TIPS) is an important technique for treating complications related to portal hypertension in patients with cirrhosis, and the number of publications in the TIPS field continues to rise. AIM: To facilitate an understanding of the research status and hotspots in the field of TIPS using CiteSpace bibliometric analysis. METHODS: CiteSpace is a software that depicts the strength of relationships through graphics and connections with diverse functionalities and can be used to analyze the status and hotspots of areas of research. Articles on TIPS in the Web of Science Core Collection were retrieved, and CiteSpace software was used to visualize and analyze the number of publications, journals, countries, institutions, authors, keywords, and citations. RESULTS: A total of 985 relevant documents were included in the analysis. From January 2013 to December 2022, the number of publications increased annually. The journal, institution, and author with the greatest number of publications in the field of TIPS are the Journal of Vascular and Interventional Radiology, the University of Bonn, and Jonel Trebicka, respectively. The main keywords used in this field are "transjugular intrahepatic portosystemic shunt", "portal hypertension", "cirrhosis", "management", "stent", "hepatic encephalopathy", "refractory ascite", "survival", "risk", and "variceal bleeding". The greatest obstacle to TIPS placement is currently the occurrence of hepatic encephalopathy. The research hotspots are the mechanism, risk factors, management, and control of hepatic encephalopathy. CONCLUSION: This bibliometric analysis reported the research status and hotspots of TIPS. Research on postoperative hepatic encephalopathy is the research hotspot in this field.

5.
Sci China Life Sci ; 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39428430

RESUMEN

D-serine and D-aspartate are involved in N-methyl-D-aspartate receptor (NMDAR)-related physiological and pathological processes. D-aminoacyl-tRNA deacylase 1 (DTD1) may biochemically contribute to D-serine or D-aspartate production. However, it is unclear thus far whether DTD1 regulates D-serine or D-aspartate content in neurobiological processes. In the present research, we found that DTD1 was essential to maintain the D-serine or D-aspartate homeostasis, which was consistent with the phenomenon that DTD1-deficiency resulted in changes in the quantity changes of functional NMDAR subunits in postsynaptic compartments. Moreover, DTD1 played a considerable role in regulating dendritic morphology and synaptic structure. As a consequence, DTD1 affected neurobiological events, including the synaptic strength of the CA3-to-CA1 circuit, dendritic spine density of hippocampal pyramidal neurons, and behavioral performance of mice in the Morris water maze. These findings highlight the important role of DTD1 in synaptic transmission, neuronal morphology, and spatial learning and memory and suggest an undisclosed mechanism of DTD1 that participates the regulation of D-serine or D-aspartate homeostasis in hippocampal neurons.

6.
Front Microbiol ; 15: 1444235, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39386365

RESUMEN

In this study, a ddPCR method for the detection of scale drop disease virus (SDDV) in yellowfin seabream (Acanthopagrus latus) was established based on Real-time fluorescence quantitative PCR detection methods and principles. The reaction conditions were optimized, and the sensitivity, specificity, accuracy, and reproducibility were assessed. The results showed that threshold line position was determined to be 1900 by the ddPCR method; the optimum annealing temperature for SDDV detection by the ddPCR method was 60°C; the limit of detection was 1.4-1.7 copies/µL; the results of specific detection of other common viruses, except for SDDV specific amplification, were all negative; and the relative standard deviation (RSD) for the reproducibility validation was 0.77%. The samples of yellowfin seabream (Acanthopagrus latus) liver, spleen, kidney, heart, intestine, brain, blood, muscle, skin and ascites with three replicates, respectively, were tested using the ddPCR method, and the results were consistent with clinical findings. The ddPCR method established in this study has the advantages of high sensitivity, high specificity, good reproducibility and simple steps for the quantitative detection of SDDV, which could be used for the nucleic acid detection of clinical SDDV samples, and provided a new quantitative method for the diagnosis of yellowfin seabream SDDV in the early stage of pathogenesis.

7.
J Thorac Dis ; 16(8): 5274-5284, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39268132

RESUMEN

Background: There is a shortage of reliable predictive models to provide valuable prognostic information for early esophageal squamous cell carcinoma (ESCC) without lymph node metastasis (LNM). We aimed to develop and validate a nomogram using the prognostic factors in T1N0 ESCC patients. Methods: Patients with pathological T1N0 ESCC who underwent esophagectomy between 2014 and 2021 at three institutes were reviewed. The prognostic factors were evaluated by Cox proportional hazards model and a nomogram was developed. Patients were divided into high- and low-risk groups based on cut-off value of total points in the nomogram. Overall survival (OS) was estimated by the Kaplan-Meier method and compared using the log-rank test. Results: A total of 275 patients were included and split into training (n=180) and external validation (n=95) cohorts. In the training cohort, multivariable analysis showed that the surgical approach, T1 substage, and carcinoembryonic antigen (CEA) level were independent prognostic factors. The developed nomogram had relatively high performance, with the area under the receiver operating characteristic (ROC) curve (AUC) of 0.783, 0.711 and 0.612 for 1-, 3-, and 5-year OS, respectively. The calibration curves showed that the predicted probability was in good agreement with the actual probability. Forty-seven was determined as cut-off value of total points. High-risk group (n=148) showed a significant poor OS than low-risk group (n=127) (P<0.001). Conclusions: Left surgical approach, stage T1b, and higher CEA were associated with poorer prognosis in T1N0 ESCC patients. The nomogram demonstrated a good performance to predict the individual survival.

8.
Toxics ; 12(9)2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39330574

RESUMEN

Inflammation is associated with an increased risk of developing various cancers in both animals and humans, primarily solid tumors but also myeloproliferative neoplasms (MPNs), myelodysplastic syndromes (MDS), and acute myeloid leukemia (AML). Multi-walled carbon nanotubes (MWCNTs), a type of carbon nanotubes (CNTs) increasingly used in medical research and other fields, are leading to a rising human exposure. Our study demonstrated that exposing mice to MWCNTs accelerated the progression of spontaneous MOL4070LTR virus-induced leukemia. Additionally, similar exposures elevated pro-inflammatory cytokines such as interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α and induced reactive oxygen species (ROS) in a murine macrophage cell line. These effects were significantly reduced in immunodeficient mice and when mice were treated with methoxypolyethylene glycol amine (PEG)-modified MWCNTs. These findings underscore the necessity of evaluating the safety of MWCNTs, particularly for those with hematologic cancers.

9.
Chin Med Sci J ; 39(3): 162-170, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39318276

RESUMEN

OBJECTIVES: To identify the 5' untranslated region of Zika virus (ZIKV 5'UTR) RNA-binding proteins and to investigate the impact of the binding protein on the activity of internal ribosomal entry site (IRES) located in ZIKV 5'UTR and virus production. METHODS: Interacting proteins in U251 cells were captured using tRSA-tagged ZIKV 5'UTR RNA and tRSA-ZIKV 5'UTR RNA-binding proteins were visualized by SDS-PAGE silver staining. Subsequently, liquid chromatography-tandem mass spectrometry (LC-MS/MS), bioinformatics analysis, and Western blot were used to identify the candidate proteins binding to ZIKV 5'UTR. Dicistronic expression assay and plaque forming assay were performed to analyze the effect of the binding protein on ZIKV IRES activity and ZIKV production, respecitvely. RESULTS: tRSA RNA pull-down assay, LC-MS/MS, and Western blot analysis showed that polypyrimidine tract-binding protein (PTB) bound to the ZIKV 5'UTR. Furthermore, dual luciferase reporter assay revealed that overexpression of PTB significantly enhanced the IRES activity of ZIKV (t = 10.220, P < 0.001), while PTB knockdown had the opposite effect (t = 4.897, P < 0.01). Additionally, virus plaque forming assay demonstrated that up-regulation of PTB expression significantly enhanced viral titer (t = 6.400, P < 0.01), whereas reducing PTB expression level weakened virus infectivity (t = 5.055, P < 0.01). CONCLUSIONS: PTB positively interacts with the ZIKV 5'UTR and enhances IRES activity and virus production.


Asunto(s)
Regiones no Traducidas 5' , Sitios Internos de Entrada al Ribosoma , Proteína de Unión al Tracto de Polipirimidina , Virus Zika , Virus Zika/genética , Virus Zika/metabolismo , Virus Zika/fisiología , Regiones no Traducidas 5'/genética , Proteína de Unión al Tracto de Polipirimidina/metabolismo , Proteína de Unión al Tracto de Polipirimidina/genética , Sitios Internos de Entrada al Ribosoma/genética , Humanos , Biosíntesis de Proteínas , Infección por el Virus Zika/metabolismo , Infección por el Virus Zika/virología , Infección por el Virus Zika/genética , Unión Proteica
10.
PLoS One ; 19(9): e0311129, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39348418

RESUMEN

This article explores the estimation of Shannon entropy and Rényi entropy based on the generalized inverse exponential distribution under the condition of stepwise Type II truncated samples. Firstly, we analyze the maximum likelihood estimation and interval estimation of Shannon entropy and Rényi entropy for the generalized inverse exponential distribution. In this process, we use the bootstrap method to construct confidence intervals for Shannon entropy and Rényi entropy. Next, we select the gamma distribution as the prior distribution and apply the Lindley approximation algorithm to calculate `estimates of Shannon entropy and Rényi entropy under different loss functions including Linex loss function, entropy loss function, and DeGroot loss function respectively. Afterwards, simulation is used to calculate estimates and corresponding mean square errors of Shannon entropy and Rényi entropy in GIED model. The research results show that under DeGroot loss function, estimation accuracy of Shannon entropy and Rényi entropy for generalized inverse exponential distribution is relatively high, overall Bayesian estimation performs better than maximum likelihood estimation. Finally, we demonstrate effectiveness of our estimation method in practical applications using a set of real data.


Asunto(s)
Algoritmos , Teorema de Bayes , Entropía , Modelos Estadísticos , Funciones de Verosimilitud , Humanos , Simulación por Computador
11.
Dev Psychobiol ; 66(7): e22544, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39236223

RESUMEN

Past studies in animal models have extensively investigated the impact of early life experiences on behavioral development, yet relatively few have specifically examined the implications of peripubertal experiences on the evolution of competitive behavior across distinct stages of adulthood. In the current research, we probed potential differences in competitive behavior during emerging adulthood (3 months old) and middle adulthood (12 months old) in 81 Sprague-Dawley male rats exposed to three different peripubertal (postnatal Days 37-60) environments: an enriched environment (EE), a chronic unpredictable mild stress (CUMS) condition, and a control condition. Anxiety-like behavior served as a positive control in our study. Results revealed significant variations in competitive behavior among the groups during emerging adulthood. The EE group displayed the least anxiety and outperformed their peers in food-reward-oriented competition, whereas the CUMS group excelled in status-driven, agonistic competition. However, these behavioral differentiations gradually attenuated by middle adulthood, at which point the control group began to show an advantage. Our findings suggest that although peripubertal experiences significantly shape competitive behavior in the emerging adulthood stage, this effect diminishes over time and is nearly non-detectable during mid-adulthood, underscoring the fluidity of behavioral development and demonstrating that the effects of peripubertal experiences can be modulated by subsequent life experiences.


Asunto(s)
Conducta Animal , Conducta Competitiva , Ratas Sprague-Dawley , Estrés Psicológico , Animales , Masculino , Ratas , Conducta Competitiva/fisiología , Conducta Animal/fisiología , Estrés Psicológico/fisiopatología , Ansiedad/fisiopatología , Ambiente , Factores de Edad
12.
Behav Brain Sci ; 47: e169, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39311504

RESUMEN

This commentary examines the synergy between meta-learned models of cognition and integrative learning in enhancing animal and human learning outcomes. It highlights three integrative learning modes - holistic integration of parts, top-down reasoning, and generalization with in-depth analysis - and their alignment with meta-learned models of cognition. This convergence promises significant advances in educational practices, artificial intelligence, and cognitive neuroscience, offering a novel perspective on learning and cognition.


Asunto(s)
Cognición , Aprendizaje , Humanos , Animales , Cognición/fisiología , Aprendizaje/fisiología , Inteligencia Artificial , Modelos Psicológicos , Generalización Psicológica/fisiología
13.
Mar Biotechnol (NY) ; 26(5): 975-990, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39138702

RESUMEN

Antimicrobial peptides (AMPs) are crucial in the humoral immunity aspect of invertebrates' innate immune systems. However, studies on AMP discovery in the Pacific white shrimp (Litopenaeus vannamei) using omics data have been limited. Addressing the growing concern of antibiotic resistance in aquaculture, this study focused on the identification and characterization of AMPs in L. vannamei using advanced genomic and transcriptomic techniques. The genome of L. vannamei was performed to predict and identify a total of 754 AMP-derived genes, distributed across most chromosomes and spanning 24 distinct AMP families, and further identified 236 AMP-derived genes at the mRNA level in hemocytes. A subset of 20 chemically synthesized peptides, derived from these genes, exhibited significant antimicrobial activity, with over 85% showing effectiveness against key bacterial strains such as Staphylococcus aureus and Vibrio parahaemolyticus. The expression patterns of these AMPs were also investigated in different shrimp tissues and at various infection stages, revealing dynamic responses to pathogenic challenges. These findings highlight the significant potential of AMPs in L. vannamei as novel, effective alternatives to traditional antibiotics in aquaculture, offering insights into their diverse structural properties and biological functions. Together, this comprehensive characterization of the AMP repertoire in L. vannamei demonstrates the efficacy of using omics data for AMP discovery and lays the groundwork for their potential applications.


Asunto(s)
Péptidos Antimicrobianos , Penaeidae , Staphylococcus aureus , Transcriptoma , Vibrio parahaemolyticus , Animales , Penaeidae/genética , Penaeidae/microbiología , Péptidos Antimicrobianos/farmacología , Péptidos Antimicrobianos/genética , Péptidos Antimicrobianos/química , Vibrio parahaemolyticus/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Genómica , Perfilación de la Expresión Génica , Hemocitos/metabolismo , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/farmacología , Proteínas de Artrópodos/química , Inmunidad Innata/genética , Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/metabolismo
14.
Clin Transl Oncol ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39133386

RESUMEN

PPM1F has been shown to play diverse biological functions in the progression of multiple tumors. PPM1F controls the T788/T789 phosphorylation switch of ITGB1 and regulates integrin activity. However, the impacts of PPM1F and ITGB1 on ovarian cancer (OV) progression remain unclear. Whether there is such a regulatory relationship between PPM1F and ITGB1 in ovarian cancer has not been studied. Therefore, the purpose of this study is to elucidate the function and the mechanism of PPM1F in ovarian cancer. The expression level and the survival curve of PPM1F were analyzed by databases. Gain of function and loss of function were applied to explore the function of PPM1F in ovarian cancer. A tumor formation assay in nude mice showed that knockdown of PPM1F inhibited tumor formation. We tested the effect of PPM1F on ITGB1 dephosphorylation in ovarian cancer cells by co-immunoprecipitation and western blotting. Loss of function was applied to investigate the function of ITGB1 in ovarian cancer. ITGB1-mut overexpression promotes the progression of ovarian cancer. Rescue assays showed the promoting effect of ITGB1-wt on ovarian cancer is attenuated due to the dephosphorylation of ITGB1-wt by PPM1F. PPM1F and ITGB1 play an oncogene function in ovarian cancer. PPM1F regulates the phosphorylation of ITGB1, which affects the occurrence and development of ovarian cancer.

16.
Proc Natl Acad Sci U S A ; 121(35): e2400385121, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39167602

RESUMEN

Type 2 diabetes (T2D) is potentially linked to disordered tryptophan metabolism that attributes to the intricate interplay among diet, gut microbiota, and host physiology. However, underlying mechanisms are substantially unknown. Comparing the gut microbiome and metabolome differences in mice fed a normal diet (ND) and high-fat diet (HFD), we uncover that the gut microbiota-dependent tryptophan metabolite 5-hydroxyindole-3-acetic acid (5-HIAA) is present at lower concentrations in mice with versus without insulin resistance. We further demonstrate that the microbial transformation of tryptophan into 5-HIAA is mediated by Burkholderia spp. Additionally, we show that the administration of 5-HIAA improves glucose intolerance and obesity in HFD-fed mice, while preserving hepatic insulin sensitivity. Mechanistically, 5-HIAA promotes hepatic insulin signaling by directly activating AhR, which stimulates TSC2 transcription and thus inhibits mTORC1 signaling. Moreover, T2D patients exhibit decreased fecal levels of 5-HIAA. Our findings identify a noncanonical pathway of microbially producing 5-HIAA from tryptophan and indicate that 5-HIAA might alleviate the pathogenesis of T2D.


Asunto(s)
Dieta Alta en Grasa , Microbioma Gastrointestinal , Resistencia a la Insulina , Hígado , Diana Mecanicista del Complejo 1 de la Rapamicina , Receptores de Hidrocarburo de Aril , Transducción de Señal , Triptófano , Proteína 2 del Complejo de la Esclerosis Tuberosa , Animales , Dieta Alta en Grasa/efectos adversos , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Triptófano/metabolismo , Microbioma Gastrointestinal/efectos de los fármacos , Ratones , Receptores de Hidrocarburo de Aril/metabolismo , Hígado/metabolismo , Humanos , Proteína 2 del Complejo de la Esclerosis Tuberosa/metabolismo , Proteína 2 del Complejo de la Esclerosis Tuberosa/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/microbiología , Masculino , Ratones Endogámicos C57BL , Obesidad/metabolismo , Obesidad/microbiología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico
17.
ACS Pharmacol Transl Sci ; 7(8): 2350-2357, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39144563

RESUMEN

Riboflavin transporter 3 (RFVT3) represents a potential cardioprotective biotarget in energetic metabolism reprogramming after myocardial infarction/reperfusion (MI/R). This study investigated the feasibility of noninvasive real-time quantification of RFVT3 expression after MI/R with an radiolabeled probe 18F-RFTA in a preclinical rat model of MI/R. The tracer 18F-RFTA was radio-synthesized manually and characterized on the subjects of radiolabeling yield, radiochemical purity, and stability in vivo. MI/R and sham-operated rat models were confirmed by cardiac magnetic resonance imaging (cMRI) and single-photon-emission computed tomography (SPECT) myocardial perfusion imaging (MPI) with technetium-99m sestamibi (99mTc-MIBI). Positron emission tomography (PET) imaging of MI/R and sham-operated rat models were conducted with 18F-RFTA. Ex vivo autoradiography and RFVT3 immunohistochemical (IHC) staining were conducted to verify the RFVT3 expression in infarcted and normal myocardium. 18F-RFTA injection was prepared with high radiochemical purity (>95%) and kept stable in vitro and in vivo. 18F-RFTA PET revealed significant uptake in the infarcted myocardium at 8 h after reperfusion, as confirmed by lower 99mTc-MIBI perfusion and decreased intensity of cMRI. Conversely, there were only the tiniest uptakes in the normal myocardium and blocked infarcted myocardium, which was further corroborated by ex vivo autoradiography. The RFVT3 expression was further confirmed by IHC staining in the infarcted and normal myocardium. We first demonstrate the feasibility of imaging RFVT3 in infarcted myocardium. 18F-RFTA is an encouraging PET probe for imaging cardioprotective biotarget RFVT3 in mitochondrial energetic metabolism reprogramming after myocardial infarction. Noninvasive imaging of cardioprotective biotarget RFVT3 has potential value in the diagnosis and therapy of patients with MI.

18.
mBio ; 15(8): e0141124, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-38980040

RESUMEN

Cyclic purine nucleotides are important signal transduction molecules across all domains of life. 3',5'-cyclic di-adenosine monophosphate (c-di-AMP) has roles in both prokaryotes and eukaryotes, while the signals that adjust intracellular c-di-AMP and the molecular machinery enabling a network-wide homeostatic response remain largely unknown. Here, we present evidence for an acetyl phosphate (AcP)-governed network responsible for c-di-AMP homeostasis through two distinct substrates, the diadenylate cyclase DNA integrity scanning protein (DisA) and its newly identified transcriptional repressor, DasR. Correspondingly, we found that AcP-induced acetylation exerts these regulatory actions by disrupting protein multimerization, thus impairing c-di-AMP synthesis via K66 acetylation of DisA. Conversely, the transcriptional inhibition of disA was relieved during DasR acetylation at K78. These findings establish a pivotal physiological role for AcP as a mediator to balance c-di-AMP homeostasis. Further studies revealed that acetylated DisA and DasR undergo conformational changes that play crucial roles in differentiation. Considering the broad distribution of AcP-induced acetylation in response to environmental stress, as well as the high conservation of the identified key sites, we propose that this unique regulation of c-di-AMP homeostasis may constitute a fundamental property of central circuits in Actinobacteria and thus the global control of cellular physiology.IMPORTANCESince the identification of c-di-AMP is required for bacterial growth and cellular physiology, a major challenge is the cell signals and stimuli that feed into the decision-making process of c-di-AMP concentration and how that information is integrated into the regulatory pathways. Using the bacterium Saccharopolyspora erythraea as a model, we established that AcP-dependent acetylation of the diadenylate cyclase DisA and its newly identified transcriptional repressor DasR is involved in coordinating environmental and intracellular signals, which are crucial for c-di-AMP homeostasis. Specifically, DisA acetylated at K66 directly inactivates its diadenylate cyclase activity, hence the production of c-di-AMP, whereas DasR acetylation at K78 leads to increased disA expression and c-di-AMP levels. Thus, AcP represents an essential molecular switch in c-di-AMP maintenance, responding to environmental changes and possibly hampering efficient development. Therefore, AcP-mediated posttranslational processes constitute a network beyond the usual and well-characterized synthetase/hydrolase governing c-di-AMP homeostasis.


Asunto(s)
Proteínas Bacterianas , Fosfatos de Dinucleósidos , Regulación Bacteriana de la Expresión Génica , Homeostasis , Acetilación , Fosfatos de Dinucleósidos/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Actinobacteria/metabolismo , Actinobacteria/genética , Organofosfatos/metabolismo , Procesamiento Proteico-Postraduccional , Transducción de Señal , Proteínas Represoras/metabolismo , Proteínas Represoras/genética
19.
World J Clin Cases ; 12(19): 3918-3924, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38994313

RESUMEN

BACKGROUND: Amyloidosis is a rare disorder that can be classified into various types, and the most common type is the systemic light chain type. The prognosis of this disease is extremely poor. In general, amyloidosis mainly affects the kidneys and heart and manifests as abnormal proliferation of clonal plasma cells. Cases in which the liver is the primary organ affected by amyloidosis, as in this report, are less common in clinical practice. CASE SUMMARY: A 62-year-old man was admitted with persistent liver dysfunction of unknown cause and poor treatment outcomes. His condition persisted, and he developed chronic liver failure, with severe cholestasis in the later stage that was gradually accompanied by renal injury. Ultimately, he was diagnosed with hepatic amyloidosis through liver biopsy and pathological examination. CONCLUSION: Hepatic amyloidosis rarely occurs in the clinic, and liver biopsy and pathological examination can assist in the accurate and effective diagnosis of this condition.

20.
Front Vet Sci ; 11: 1343768, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38887537

RESUMEN

The objective of this study is to review different methods to screen for the optimal model for preventing and treating chicken glandular and muscular gastritis syndrome. Twenty-four 40-day-old specific pathogen-free (SPF) chickens were randomly allocated into four groups (N = 6): polyethylene glycol + ammonium chloride group (M1 group), acetic acid + rhubarb group (M2 group), polyethylene glycol + rhubarb group (M3 group), and control group. The control group had free access to water, while the remaining groups received different doses of molding reagents added to their drinking water. The animal models were assessed based on clinical manifestations, histopathology findings, serological analysis, and composition of intestinal microbiota to establish an optimal approach for constructing an avian model of glandular and muscular gastritis. The SPF chickens in each model group exhibited typical symptoms of glandular and muscular gastritis, poor spirit, yellow loose stools with undigested feed, and enlargement and ulceration of the glandular and muscular stomach. Among these groups, the M3 group had the highest incidence rate of 100%. Compared to the control group, the body weight and body temperature of the chicken in the three model groups were reduced, and the glandular and muscular stomachs and duodenum showed different degrees of bleeding, mucosal abscission, and other pathological injuries. Additionally, the levels of serum IL-2 and α-amylase activity decreased while the content of IL-4 increased. After conducting 16s rDNA sequencing, it was observed that the abundance of Bacteroides, Faecalibacterium, and Ruminococcaceae UCG-014 was significantly increased in the model group compared to the control group. Conversely, there was a notable decrease in the levels of Megamonas and Lactobacillus, which are speculated to be associated with arachidonic acid metabolism, the NF-κB signaling pathway, and TNF signaling pathways. The combination of polyethylene glycol and rhubarb emerged as the most effective method for establishing the glandular and muscular gastritis model in SPF chickens. This constructed chicken model displayed distinct signs of damage to the glandular and muscular stomach, inflammatory response, and disturbance in the intestinal flora, thereby providing a foundation for future research on the prevention and treatment of this syndrome.

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