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1.
Cardiovasc Diabetol ; 23(1): 30, 2024 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-38218819

RESUMO

BACKGROUND: Individuals who are overweight or obese often develop insulin resistance, mediation of the association between body mass index (BMI) and stroke risk through the triglyceride-glucose index (TyG) seems plausible but has not been investigated. This study aims to examine whether TyG mediates associations of BMI with stroke risk and the extent of interaction or joint relations of TyG and BMI with stroke outcome. METHODS: The China Health and Retirement Longitudinal Study, initiated in 2011, is a nationally representative, ongoing prospective cohort study involving 8 231 middle-aged and older Chinese adults without a stroke history at baseline. Exposures examined include BMI and the TyG, the latter being the logarithmized product of fasting triglyceride and glucose concentrations. The primary study outcome is stroke incidence, as determined through self-reports, with a follow-up period extending from June 1, 2011, to June 30, 2018. RESULTS: Of the 8 231 participants, 3 815 (46.3%) were men; mean (SD) age was 59.23 (9.32) years. During a median follow-up of 7.1 years, 585 (7.1%) participants developed stroke. The TyG was found to mediate the association between BMI and incident stroke, proportions mediated were 16.3% for BMI in the 24.0-27.9 kg/m2 group and 53.8% for BMI ≥ 28.0 kg/m2 group. No significant multiplicative and additive interactions were found between BMI and TyG on incident stroke (Additive: RERI = 1.78, 95% CI - 1.29-4.86; Multiplicative, HR = 1.40, 95% CI 0.86-2.27). HRs for individuals with BMI ≥ 28.0 kg/m2 and quartile 4 of TyG compared with those with BMI < 24.0 kg/m2 and quartile 1 of TyG were 2.05 (95% CI 1.37-3.06) for incident stroke. Combining BMI and TyG enhanced predictive performance for stroke when compared to their individual (AUCBMI+TyG vs AUCBMI vs AUCTyG, 0.602 vs 0.581 vs 0.583). CONCLUSIONS: TyG appeared to be associated with stroke risk and mediates more than 50% of the total association between BMI and stroke in middle-aged and older Chinese adults. Public health efforts aiming at the reduction of body weight might decrease the stroke risk due to insulin resistance and the burden of stroke.


Assuntos
Resistência à Insulina , Acidente Vascular Cerebral , Adulto , Masculino , Pessoa de Meia-Idade , Humanos , Idoso , Feminino , Índice de Massa Corporal , Estudos Longitudinais , Estudos Prospectivos , China/epidemiologia , Glucose , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Triglicerídeos , Glicemia , Fatores de Risco , Biomarcadores
2.
Nucleic Acids Res ; 50(17): 9858-9872, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36095124

RESUMO

RNA molecules harbor diverse modifications that play important regulatory roles in a variety of biological processes. Over 150 modifications have been identified in RNA molecules. N6-methyladenosine (m6A) and 1-methyladenosine (m1A) are prevalent modifications occurring in various RNA species of mammals. Apart from the single methylation of adenosine (m6A and m1A), dual methylation modification occurring in the nucleobase of adenosine, such as N6,N6-dimethyladenosine (m6,6A), also has been reported to be present in RNA of mammals. Whether there are other forms of dual methylation modification occurring in the nucleobase of adenosine other than m6,6A remains elusive. Here, we reported the existence of a novel adenosine dual methylation modification, i.e. 1,N6-dimethyladenosine (m1,6A), in tRNAs of living organisms. We confirmed that m1,6A is located at position 58 of tRNAs and is prevalent in mammalian cells and tissues. The measured level of m1,6A ranged from 0.0049% to 0.047% in tRNAs. Furthermore, we demonstrated that TRMT6/61A could catalyze the formation of m1,6A in tRNAs and m1,6A could be demethylated by ALKBH3. Collectively, the discovery of m1,6A expands the diversity of RNA modifications and may elicit a new tRNA modification-mediated gene regulation pathway.


Assuntos
Adenosina , RNA de Transferência , Adenosina/genética , Adenosina/metabolismo , Animais , Mamíferos/genética , Mamíferos/metabolismo , Metilação , RNA/genética , RNA/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo
3.
Ecotoxicol Environ Saf ; 281: 116607, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38908055

RESUMO

Deoxynivalenol (DON), commonly known as vomitoxin, is a mycotoxin produced by fungi and is frequently found as a contaminant in various cereal-based food worldwide. While the harmful effects of DON have been extensively studied in different tissues, its specific impact on the proliferation of skeletal muscle cells remains unclear. In this study, we utilized murine C2C12 myoblasts as a model to explore the influence of DON on their proliferation. Our observations indicated that DON exhibits dose-dependent toxicity, significantly inhibiting the proliferation of C2C12 cells. Through the application of RNA-seq analysis combined with gene set enrichment analysis, we identified a noteworthy downregulation of genes linked to the extracellular matrix (ECM) and condensed chromosome. Concurrently with the reduced expression of ECM genes, immunostaining analysis revealed notable changes in the distribution of fibronectin, a vital ECM component, condensing into clusters and punctate formations. Remarkably, the exposure to DON induced the formation of multipolar spindles, leading to the disruption of the normal cell cycle. This, in turn, activated the p53-p21 signaling pathway and ultimately resulted in apoptosis. These findings contribute significant insights into the mechanisms through which DON induces toxicity within skeletal muscle cells.

4.
J Antimicrob Chemother ; 78(7): 1632-1636, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37202829

RESUMO

OBJECTIVES: Contezolid acefosamil is a novel O-acyl phosphoramidate prodrug of contezolid. In the current study, we aimed to systemically evaluate the efficacy of contezolid acefosamil against infections caused by multiple Gram-positive pathogens, and compare the efficacy of the prodrug by oral and intravenous administrations. METHODS: The in vivo pharmacodynamic efficacy of contezolid acefosamil was evaluated in mouse models of systemic (with five S. aureus, three S. pneumoniae and two S. pyogenes bacterial isolates) and thigh (with two S. aureus isolates) infections using linezolid as the reference agent. RESULTS: In both models, contezolid acefosamil administrated either orally or intravenously, demonstrated high antibacterial efficacy similar to linezolid, and the antibacterial efficacy of oral and intravenous contezolid acefosamil were comparable. CONCLUSIONS: The high aqueous solubility and great efficacy of contezolid acefosamil support its clinical development as an injectable and oral antibiotic suitable for serious Gram-positive infections.


Assuntos
Pró-Fármacos , Animais , Camundongos , Linezolida , Pró-Fármacos/farmacologia , Staphylococcus aureus , Antibacterianos/uso terapêutico , Administração Intravenosa , Testes de Sensibilidade Microbiana , Administração Oral
5.
Cardiovasc Diabetol ; 22(1): 254, 2023 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-37716947

RESUMO

BACKGROUND: Stroke was reported to be highly correlated with the triglyceride glucose-body mass index (TyG-BMI). Nevertheless, literature exploring the association between changes in the TyG-BMI and stroke incidence is scant, with most studies focusing on individual values of the TyG-BMI. We aimed to investigate whether changes in the TyG-BMI were associated with stroke incidence. METHODS: Data were obtained from the China Health and Retirement Longitudinal Study (CHARLS), which is an ongoing nationally representative prospective cohort study. The exposures were changes in the TyG-BMI and cumulative TyG-BMI from 2012 to 2015. Changes in the TyG-BMI were classified using K-means clustering analysis, and the cumulative TyG-BMI was calculated as follows: (TyG-BMI2012 + TyG-BMI2015)/2 × time (2015-2012). Logistic regressions were used to determine the association between different TyG-BMI change classes and stroke incidence. Meanwhile, restricted cubic spline regression was applied to examine the potential nonlinear association of the cumulative TyG-BMI and stroke incidence. Weighted quantile sum regression was used to provide a comprehensive explanation of the TyG-BMI by calculating the weights of FBG, triglyceride-glucose (TG), and BMI. RESULTS: Of the 4583 participants (mean [SD] age at baseline, 58.68 [9.51] years), 2026 (44.9%) were men. During the 3 years of follow-up, 277 (6.0%) incident stroke cases were identified. After adjusting for potential confounders, compared to the participants with a consistently low TyG-BMI, the OR for a moderate TyG-BMI with a slow rising trend was 1.01 (95% CI 0.65-1.57), the OR for a high TyG-BMI with a slow rising trend was 1.62 (95% CI 1.11-2.32), and the OR for the highest TyG-BMI with a slow declining trend was 1.71 (95% CI 1.01-2.89). The association between the cumulative TyG-BMI and stroke risk was nonlinear (Passociation = 0.017; Pnonlinearity = 0.012). TG emerged as the primary contributor when the weights were assigned to the constituent elements of the TyG-BMI (weight2012 = 0.466; weight2015 = 0.530). CONCLUSIONS: Substantial changes in the TyG-BMI are independently associated with the risk of stroke in middle-aged and older adults. Monitoring long-term changes in the TyG-BMI may assist with the early identification of individuals at high risk of stroke.


Assuntos
Glicemia , Índice de Massa Corporal , População do Leste Asiático , Acidente Vascular Cerebral , Triglicerídeos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Glucose/análise , Estudos Longitudinais , Estudos Prospectivos , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Glicemia/análise , Risco
6.
Bioorg Chem ; 134: 106424, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36868126

RESUMO

Cell-penetrating peptides (CPPs) are prominent scaffolds for drug developments and related research, particularly the endocytic delivery of biomacromolecules. Effective cargo release from endosomes prior to lysosomal degradation is a crucial step, where the rational design and selection of CPPs remains a challenge and calls for deeper mechanistic understandings. Here, we have investigated a strategy of designing CPPs that selectively disrupt endosomal membranes based on bacterial membrane targeting sequences (MTSs). Six synthesized MTS peptides all exhibit cell-penetrating abilities, among which two d-peptides (d-EcMTS and d-TpMTS) are able to escape from endosomes and localize at ER after entering the cell. The utility of this strategy has been demonstrated by the intracellular delivery of green fluorescent protein (GFP). Together, these results suggest that the large pool of bacterial MTSs may be a rich source for the development of novel CPPs.


Assuntos
Peptídeos Penetradores de Células , Peptídeos Penetradores de Células/química , Endossomos/química , Endossomos/metabolismo
7.
Anal Chem ; 94(24): 8740-8747, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35678728

RESUMO

RNA molecules contain diverse modifications that play crucial roles in a wide variety of biological processes. Adenosine-to-inosine (A-to-Ino) RNA editing is one of the most prevalent modifications among all types of RNA. Abnormal A-to-InoRNA editing has been demonstrated to be associated with many human diseases. Identification of A-to-Ino editing sites is indispensable to deciphering their biological roles. Herein, by employing the unique property of human endonuclease V (hEndoV), we proposed a hEndoV-mediated sequencing (hEndoV-seq) method for the single-base resolution detection of A-to-InoRNA editing sites. In this approach, the terminal 3'OH of RNA is first blocked by 3'-deoxyadenosine (3'-deoxy-A). Specific cleavage of Ino sites by hEndoV protein produces new terminal 3'OH, which can be identified by sequencing analysis, and therefore offers the site-specific detection of Ino in RNA. The principle of hEndoV-seq is straightforward and the analytical procedure is simple. No chemical reaction is involved in the sequencing library preparation. The whole procedure in hEndoV-seq is carried out under mild conditions and RNA is not prone to degradation. Taken together, the proposed hEndoV-seq method is capable of site-specific identification of A-to-Ino editing in RNA, which provides a valuable tool for elucidating the functions of A-to-Ino editing in RNA.


Assuntos
Edição de RNA , RNA , Adenosina/metabolismo , Endonucleases/metabolismo , Humanos , Inosina , RNA/metabolismo
8.
Anal Chem ; 94(11): 4747-4755, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35266699

RESUMO

The discovery of reversible modifications in messenger RNA (mRNA) opens new research directions in RNA modification-mediated epigenetic regulation. Yeast is an extensively used model organism in molecular biology. Systematic investigation and profiling of modifications in yeast mRNA would promote our understanding of the physiological regulation mechanisms in yeast. However, due to the high abundance of ribosomal RNA (rRNA) and transfer RNA (tRNA) in total RNA, isolation of low abundance of mRNA frequently suffers from the contamination of rRNA and tRNA, which will lead to the false-positive determination and inaccurate quantification of modifications in mRNA. Therefore, obtaining high-purity mRNA is critical for precise determination and accurate quantification of modifications in mRNA, especially for studies that focus on discovering new ones. Herein, we proposed a successive orthogonal isolation method by combining polyT-based purification and agarose gel electrophoresis purification for extracting high-purity mRNA. With the extracted high-purity yeast mRNA, we systemically explored the modifications in yeast mRNA by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis. The results showed that in addition to the previously reported eight kinds of modifications, two novel modifications of inosine (Ino) and 2'-O-methylinosine (Im) were identified to be prevalent in yeast mRNA. It is worth noting that Im was reported for the first time, to the best of our knowledge, to exist in living organisms in the three domains of life. Moreover, we observed that the levels of 10 kinds of modifications including Ino and Im in yeast mRNA exhibited dynamic change at different growth stages of yeast cells. Furthermore, Im in mRNA showed a significant decrease while in response to H2O2 treatment. These results indicated that the two newly identified modifications in yeast mRNA were involved in yeast cell growth and response to environmental stress. Taken together, we reported two new modifications of Ino and Im in yeast mRNA, which expends the diversity of RNA modifications in yeast and also suggests new regulators for modulating yeast physiological functions.


Assuntos
Saccharomyces cerevisiae , Espectrometria de Massas em Tandem , Cromatografia Líquida/métodos , Epigênese Genética , Peróxido de Hidrogênio , Inosina , RNA Mensageiro/genética , RNA Ribossômico , RNA de Transferência , Saccharomyces cerevisiae/genética
9.
Int J Mol Sci ; 23(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35457181

RESUMO

NUMB is an endocytic adaptor protein that contains four isoforms (p65, p66, p71 and p72) due to alternative splicing regulation. Here, we show that NUMB exon12 (E12)-skipping isoforms p65/p66 promote epithelial to mesenchymal transition (EMT) and cancer cell migration in vitro, and facilitate cancer metastasis in mice, whereas E12-included p71/p72 isoforms attenuate these effects. Mechanistically, p65/p66 isoforms significantly increase the sorting of Notch1 through early endosomes (EEs) for enhanced Notch1 activity. In contrast, p71/p72 isoforms act as negative regulators of Notch1 by ubiquitylating the Notch1 intracellular domain (N1ICD) and promoting its degradation. Moreover, we observed that the interaction between N1ICD and SMAD3 is important for their own stabilization, and for NUMB-mediated EMT response and cell migration. Either N1ICD or SMAD3 overexpression could significantly recuse the migration reduction seen in the p65/p66 knockdown, and Notch1 or SMAD3 knockdown rescued the migration advantage seen in the overexpression of p66. Taken all together, our study provides mechanistic insights into the opposite regulation of Notch1-SMAD3 crosstalk by NUMB isoforms and identifies them as critical regulators of EMT and cancer cell migration.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias , Animais , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Neoplasias/genética , Proteínas do Tecido Nervoso/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo
10.
Immunology ; 163(1): 60-73, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33421113

RESUMO

During inflammation or tissue injury, pro-inflammatory mediators attract migratory monocytes to inflammatory sites and monocyte-to-macrophage differentiation occurs to activate macrophages. We report here that PAQR11, a member of the progesterone and AdipoQ receptor family, regulates monocyte-to-macrophage differentiation in vitro and in vivo. Paqr11 gene was highly induced during monocyte-to-macrophage differentiation. Knockdown or deletion of Paqr11 inhibited monocyte differentiation but had little effect on macrophage polarization. Mechanistically, PAQR11 promoted cell survival as apoptosis was increased by Paqr11 knockdown or deletion. Activation of the MAPK signalling pathway was involved in the regulatory role of PAQR11 on monocyte differentiation and cell survival. C/EBPß regulated the expression of Paqr11 at the transcriptional level. In mice, deletion of Paqr11 gene alleviated progression of collagen-induced rheumatoid arthritis. Thus, these results provide strong evidence that PAQR11 has a function in monocyte-to-macrophage differentiation and such function is related to autoimmune disease in vivo.


Assuntos
Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Diferenciação Celular , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/metabolismo , Proteínas de Membrana/metabolismo , Monócitos/metabolismo , Animais , Apoptose , Artrite Experimental/genética , Artrite Experimental/imunologia , Artrite Experimental/patologia , Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Progressão da Doença , Regulação da Expressão Gênica , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Macrófagos/imunologia , Macrófagos/patologia , Proteínas de Membrana/genética , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Monócitos/imunologia , Monócitos/patologia , Fosforilação , Transdução de Sinais , Células THP-1
11.
Anal Chem ; 93(44): 14694-14700, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34699179

RESUMO

Atmospheric pressure mass spectrometry imaging (AP-MSI) is a powerful tool in many fields; however, there are still some difficulties to achieve high spatial resolution for AP-MSI, one of them being the need for a small ablation crater. Here, a fiber probe laser ablation (FPLA) system is introduced that uses an etched optical fiber with a sharp tip (o.d. 200 nm) to deliver ablation laser pulses to a sample surface to ablate materials with high spatial resolution. The tip-to-sample distance was adjusted to ∼10 µm using a micro-actuator having a stepping motor with submicron accuracy. The laser-ablated neutrals were post-ionized using a home-built in-line dielectric barrier discharge source, which can be interfaced to any mass spectrometer with an AP interface. Using MSI on a standard sample with a striped pattern and sections of fingernails treated with the drug methyl green zinc chloride salt, a FPLA-DBDI-MSI spatial resolution of ≈5 µm was demonstrated.


Assuntos
Pressão Atmosférica , Terapia a Laser , Diagnóstico por Imagem , Lasers , Espectrometria de Massas
12.
Anal Chem ; 93(15): 6232-6238, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33826303

RESUMO

Mass spectrometry imaging (MSI) has become a powerful tool in diverse fields, for example, life science, biomaterials, and catalysis, for its ability of in situ and real-time visualization of the location of chemical compounds in samples. Although laser ablation (LA) achieves high spatial resolution in MSI, the ion yield can be very low. We therefore combined an LA system with an ambient ion source for post-ionization and an atmospheric pressure (AP) inlet mass spectrometer to construct a novel AP-MSI platform. A dielectric barrier discharge ionization (DBDI) source is operated in the "active sampling capillary" configuration, can be coupled to any mass spectrometer with an AP interface, and possesses high ion transmission efficiency. This study presents some application examples based on LA-DBDI, a low-cost and flexible strategy for AP-MSI, which does not require any sample pretreatment, and we show MS imaging of endogenous species in a traditional Chinese herbal medicine and of a drug molecule in zebra fish tissue, with a lateral resolution of ≈20 µm.


Assuntos
Pressão Atmosférica , Terapia a Laser , Animais , Diagnóstico por Imagem , Espectrometria de Massas
13.
J Phys Chem A ; 125(23): 5022-5030, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34096293

RESUMO

Planar C2v B19- global-minimum (GM) cluster is known as a molecular Wankel motor, featuring unique chemical bonding and structural fluxionality. While the geometry, bonding, and molecular dynamics of the cluster are documented in the literature, it remains warranted to fully understand its bonding nature and unravel the mechanism behind the structural dynamics. We shall offer herein an updated bonding model on the bases of canonical molecular orbital (CMO) analysis and adaptive natural density partitioning (AdNDP), further aided by natural bond orbital (NBO) analysis and orbital composition calculations. The computational data indicate that the B19- cluster has inner 2π/6σ and outer 10π/14σ concentric 4-fold π/σ aromaticity. Being spatially isolated from each other, the inner B6 disk supports 2π and 6σ subsystems, whereas the outer B18 double-ring ribbon has 10π and 14σ subsystems. All 4-fold π/σ subsystems are intrinsically delocalized and conform to the (4n + 2) Hückel rule for aromaticity. The change of Wiberg bond index (WBI) from GM to transition-state (TS) for radial B-B links is minimal and uniform, which offers a semiquantitative measure of structural dynamics and underlies the low energy barrier.

14.
Med Sci Monit ; 27: e929711, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33941757

RESUMO

BACKGROUND Nurses who work in hospitals experience a high level of burnout and the relationship between immune variables and burnout syndrome has yet to be elucidated. The aim of the present study was to investigate the effects of job burnout on immune function in female oncology nurses in a tertiary oncology hospital in Guangxi, China. The aspects of the human immune system evaluated were humoral and cellular immunity and complement components 3 (C3) and 4 (C4). MATERIAL AND METHODS We administered the Maslach Burnout Inventory-General Survey (MBI-GS), which includes scales for emotional exhaustion, depersonalization (DP), and personal accomplishment (PA), to measure variables related to immune function in 105 female nurses in a tertiary oncology hospital in Guangxi, China. Levels of humoral immunity and C3 and C4 were detected with immune turbidimetry. Cellular immunity was assessed with indirect immunofluorescence. RESULTS A Spearman rank correlation analysis revealed that levels of C3, C4, and CD4- and CD8-positive T cells were significantly associated with burnout symptoms (P<0.05, P<0.01, and P<0.05, respectively). Furthermore, there was a correlation between demographic data and humoral and cellular immunity (both P<0.05). Multivariable linear regression analysis showed that C4 levels were closely related to DP (P<0.05) and that CD4 and CD8 levels were closely related to PA (P<0.01). CONCLUSIONS These results suggest that DP and PA have an impact on immune function, and that timely psychological and behavioral interventions can be used to reduce the degree of job burnout among nurses and regulate their immunity, thus enabling them to better serve patients.


Assuntos
Esgotamento Profissional/imunologia , Esgotamento Psicológico/imunologia , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Enfermeiras e Enfermeiros/psicologia , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Estudos Transversais , Feminino , Humanos , Enfermagem Oncológica/métodos , Estudos Prospectivos , Inquéritos e Questionários , Centros de Atenção Terciária
15.
Biochem J ; 477(2): 477-489, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31904842

RESUMO

Protein quality control is crucial for maintaining cellular homeostasis and its dysfunction is closely linked to human diseases. The post-translational protein quality control machinery mainly composed of BCL-2-associated athanogene 6 (BAG6) is responsible for triage of mislocalized membrane proteins (MLPs). However, it is unknown how the BAG6-mediated degradation of MLPs is regulated. We report here that PAQR9, a member of the Progesterone and AdipoQ receptor (PAQR) family, is able to modulate BAG6-mediated triage of MLPs. Analysis with mass spectrometry identified that BAG6 is one of the major proteins interacting with PAQR9 and such interaction is confirmed by co-immunoprecipitation and co-localization assays. The protein degradation rate of representative MLPs is accelerated by PAQR9 knockdown. Consistently, the polyubiquitination of MLPs is enhanced by PAQR9 knockdown. PAQR9 binds to the DUF3538 domain within the proline-rich stretch of BAG6. PAQR9 reduces the binding of MLPs to BAG6 in a DUF3538 domain-dependent manner. Taken together, our results indicate that PAQR9 plays a role in the regulation of protein quality control of MLPs via affecting the interaction of BAG6 with membrane proteins.


Assuntos
Homeostase/genética , Proteínas de Membrana/genética , Chaperonas Moleculares/genética , Receptores de Progesterona/genética , Humanos , Proteínas de Membrana/química , Chaperonas Moleculares/química , Ligação Proteica/genética , Domínios Proteicos/genética , Transporte Proteico/genética , Proteínas Proto-Oncogênicas c-bcl-2/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Receptores de Progesterona/química , Ubiquitinação/genética , Ubiquitinas/química , Ubiquitinas/genética
16.
J Asian Nat Prod Res ; 23(10): 992-1000, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32924591

RESUMO

One new virginiamycin derivative, 'beilunmycin' (1), and three known virginiamycin antibiotics, 16-hydroxy-virginiamycin M1 (2), virginiamycin M2 (3), and virginiamycin M1 (4), were isolated from the culture of a mangrove-derived endophytic Streptomyces sp. 2BBP-J2. The structures were characterized on the basis of their spectroscopic data, and the absolute configuration of 1 was established by ECD calculations. Compounds 1-4 exhibited antibacterial activities against Gram-positive bacteria, with MIC values in the range of 0.5-16 µg/ml. All the compounds demonstrated strong protein translation-stalling activity, with minimal concentrations detected with pDualrep2 in the range of 1.9-5.9 nmol.


Assuntos
Streptomyces , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Biossíntese de Proteínas , Streptomyces/metabolismo , Virginiamicina/metabolismo
17.
J Environ Manage ; 292: 112788, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34023787

RESUMO

Conservation of habitat patches and the related environment benefits both the focal species and human well-being. Many indices use the dispersal range to identify habitat patches with conservation priorities. However, there lacks approaches to identify environmental variables with conservation priorities (noted as target variables) in those identified patches. Therefore, this paper proposes an approach to identify environmental variables with conservation priorities in habitat patches using perception range and introduces the related assumption. It is assumed the agents select habitats based on their prior preference and perceived information in their perception ranges, which avoids the omniscient assumption of agents. Based on such assumptions, the proposed approach identifies the target variables by approximating how animals identify their habitats. It highlights the use of perception range and identifies target variables using the maximum information gain. The variables that contribute the largest reduction of uncertainty are regarded as the target variables in the habitat patches. Taking the Common Moorhen (Gallinula chloropus) living in Tianjin, China as the case, different scenarios with 100 m, 250 m and 500 m perception ranges are designed to illustrate the feasibility of the proposed approach. The proposed approach identifies the normalized vegetation index, rather than the distance to water surface, is the target variable in 42.3%, 58.9% and 72.1% habitat patches with given perception ranges. Adjustments are made on areas within the given perception range of each patch. More grid cells that has increased suitability index can be found in scenarios given 250 m perception range, which indicates the conservation area is not always the large the better. Optimizations are expected on both a better approximation method and a more thorough hypothesis of using perception range.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Aves , China , Humanos
18.
Angew Chem Int Ed Engl ; 60(50): 26378-26384, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34590769

RESUMO

Redox tailoring enzymes play key roles in generating structural complexity and diversity in type II polyketides. In chartreusin biosynthesis, the early 13 C-labeling experiments and bioinformatic analysis suggest the unusual aglycone is originated from a tetracyclic anthracyclic polyketide. Here, we demonstrated that the carbon skeleton rearrangement from a linear anthracyclic polyketide to an angular pentacyclic biosynthetic intermediate requires two redox enzymes. The flavin-dependent monooxygenase ChaZ catalyses a Baeyer-Villiger oxidation on resomycin C to form a seven-membered lactone. Subsequently, a ketoreductase ChaE rearranges the carbon skeleton and affords the α-pyrone containing pentacyclic intermediate in an NADPH-dependent manner via tandem reactions including the reduction of the lactone carbonyl group, Aldol-type reaction, followed by a spontaneous γ-lactone ring formation, oxidation and aromatization. Our work reveals an unprecedented function of a ketoreductase that contributes to generate structural complexity of aromatic polyketide.

19.
Carcinogenesis ; 41(2): 214-222, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-31140554

RESUMO

Adenosylmethionine decarboxylase 1 (AMD1) is a key enzyme involved in biosynthesis of polyamines including spermidine and spermine. The potential function of AMD1 in human gastric cancers is unknown. We analyzed AMD1 expression level in 319 human gastric cancer samples together with the adjacent normal tissues. The protein expression level of AMD1 was significantly increased in human gastric cancer samples compared with their corresponding para-cancerous histological normal tissues (P < 0.0001). The expression level of AMD1 was positively associated with Helicobactor pylori 16sRNA (P < 0.0001), tumor size (P < 0.0001), tumor differentiation (P < 0.05), tumor venous invasion (P < 0.0001), tumor lymphatic invasion (P < 0.0001), blood vessel invasion (P < 0.0001), and tumor lymph node metastasis (TNM) stage (P < 0.0001). Patients with high expression of AMD1 had a much shorter overall survival than those with normal/low expression of AMD1. Knockdown of AMD1 in human gastric cancer cells suppressed cell proliferation, colony formation and cell migration. In a tumor xenograft model, knockdown of AMD1 suppressed the tumor growth in vivo. Inhibition of AMD1 by an inhibitor SAM486A in human gastric cancer cells arrested cell cycle progression during G1-to-S transition. Collectively, our studies at the cellular, animal and human levels indicate that AMD1 has a tumorigenic effect on human gastric cancers and affect the prognosis of the patients.


Assuntos
Adenocarcinoma/patologia , Adenosilmetionina Descarboxilase/metabolismo , Carcinogênese/patologia , Infecções por Helicobacter/patologia , Neoplasias Gástricas/patologia , Adenocarcinoma/microbiologia , Adenocarcinoma/mortalidade , Adenosilmetionina Descarboxilase/antagonistas & inibidores , Adenosilmetionina Descarboxilase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Amidinas/farmacologia , Animais , Diferenciação Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/isolamento & purificação , Humanos , Indanos/farmacologia , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Poliaminas/metabolismo , Prognóstico , Estômago/patologia , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/mortalidade , Ensaios Antitumorais Modelo de Xenoenxerto
20.
J Cell Physiol ; 235(2): 1090-1102, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31256427

RESUMO

Long noncoding RNAs (lncRNAs) regulate tumor development and progression by promoting proliferation, invasion, and metastasis. The oncogenic role of lncRNA SNHG16 in hepatocellular carcinoma (HCC) has not been revealed. LncRNA SNHG16 is upregulated in HCC and correlates with poorer prognosis. Patients with high SNHG16 expression showed lower rates of overall and disease-free survival than patients with low SNHG16 expression. Multivariate Cox regression revealed that SNHG16 expression was an independent predictor of poor overall and disease-free survival. In vitro, SNHG16 promoted HCC cell proliferation, migration, and invasion while inhibiting apoptosis; in vivo, it accelerated tumor development. Altering SNHG16 expression altered levels of miR-17-5p, which in turn modified expression of p62, which has been shown to regulate the mTOR and NF-κB pathways. Indeed, altering SNHG16 expression in HCC cells activated mTOR and NF-κB signaling. These results reveal a potential mechanism for the oncogenic role of SNHG16 in HCC. SNHG16 may therefore be a promising diagnostic marker as well as therapeutic target in HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Hepáticas/metabolismo , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/metabolismo , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hepatócitos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , NF-kappa B/metabolismo , Prognóstico , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/genética
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