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1.
Plant Cell ; 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38943676

RESUMEN

The cell wall shapes plant cell morphogenesis and affects the plasticity of organ growth. However, the way in which cell wall establishment is regulated by ethylene remains largely elusive. Here, by analyzing cell wall patterns, cell wall composition and gene expression in rice (Oryza sativa, L.) roots, we found that ethylene induces cell wall thickening and the expression of cell wall synthesis-related genes, including CELLULOSE SYNTHASE-LIKE C1, 2, 7, 9, 10 (OsCSLC1, 2, 7, 9, 10) and CELLULOSE SYNTHASE A3, 4, 7, 9 (OsCESA3, 4, 7, 9). Overexpression and mutant analyses revealed that OsCSLC2 and its homologs function in ethylene-mediated induction of xyloglucan biosynthesis mainly in the cell wall of root epidermal cells. Moreover, OsCESA-catalyzed cellulose deposition in the cell wall was enhanced by ethylene. OsCSLC-mediated xyloglucan biosynthesis likely plays an important role in restricting cell wall extension and cell elongation during the ethylene response in rice roots. Genetically, OsCSLC2 acts downstream of ETHYLENE-INSENSITIVE3-LIKE1 (OsEIL1)-mediated ethylene signaling, and OsCSLC1, 2, 7, 9 are directly activated by OsEIL1. Furthermore, the auxin signaling pathway is synergistically involved in these regulatory processes. These findings link plant hormone signaling with cell wall establishment, broadening our understanding of root growth plasticity in rice and other crops.

2.
Plant Cell ; 34(11): 4366-4387, 2022 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-35972379

RESUMEN

Ethylene plays essential roles in adaptive growth of rice (Oryza sativa). Understanding of the crosstalk between ethylene and auxin (Aux) is limited in rice. Here, from an analysis of the root-specific ethylene-insensitive rice mutant mao hu zi 10 (mhz10), we identified the tryptophan aminotransferase (TAR) MHZ10/OsTAR2, which catalyzes the key step in indole-3-pyruvic acid-dependent Aux biosynthesis. Genetically, OsTAR2 acts downstream of ethylene signaling in root ethylene responses. ETHYLENE INSENSITIVE3 like1 (OsEIL1) directly activated OsTAR2 expression. Surprisingly, ethylene induction of OsTAR2 expression still required the Aux pathway. We also show that Os indole-3-acetic acid (IAA)1/9 and OsIAA21/31 physically interact with OsEIL1 and show promotive and repressive effects on OsEIL1-activated OsTAR2 promoter activity, respectively. These effects likely depend on their EAR motif-mediated histone acetylation/deacetylation modification. The special promoting activity of OsIAA1/9 on OsEIL1 may require both the EAR motifs and the flanking sequences for recruitment of histone acetyltransferase. The repressors OsIAA21/31 exhibit earlier degradation upon ethylene treatment than the activators OsIAA1/9 in a TIR1/AFB-dependent manner, allowing OsEIL1 activation by activators OsIAA1/9 for OsTAR2 expression and signal amplification. This study reveals a positive feedback regulation of ethylene signaling by Aux biosynthesis and highlights the crosstalk between ethylene and Aux pathways at a previously underappreciated level for root growth regulation in rice.


Asunto(s)
Etilenos , Ácidos Indolacéticos , Oryza , Raíces de Plantas , Triptófano-Transaminasa , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos/metabolismo , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Triptófano-Transaminasa/genética , Triptófano-Transaminasa/metabolismo
3.
PLoS Biol ; 20(10): e3001823, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36228045

RESUMEN

Bacterial lipoproteins perform a diverse array of functions including bacterial envelope biogenesis and microbe-host interactions. Lipoproteins in gram-negative bacteria are sorted to the outer membrane (OM) via the localization of lipoproteins (Lol) export pathway. The ATP-binding cassette (ABC) transporter LolCDE initiates the Lol pathway by selectively extracting and transporting lipoproteins for trafficking. Here, we report cryo-EM structures of LolCDE in apo, lipoprotein-bound, and AMPPNP-bound states at a resolution of 3.5 to 4.2 Å. Structure-based disulfide crosslinking, photo-crosslinking, and functional complementation assay verify the apo-state structure and reveal the molecular details regarding substrate selectivity and substrate entry route. Our studies snapshot 3 functional states of LolCDE in a transport cycle, providing deep insights into the mechanisms that underlie LolCDE-mediated lipoprotein sorting in E. coli.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Adenilil Imidodifosfato/metabolismo , Microscopía por Crioelectrón , Lipoproteínas/metabolismo , Transportadoras de Casetes de Unión a ATP/metabolismo , Bacterias/metabolismo , Disulfuros/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo
4.
Biol Reprod ; 110(4): 684-697, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38145487

RESUMEN

The protein kinase A (PKA) signaling pathway, which mediates protein phosphorylation, is important for sperm motility and male fertility. This process relies on A-kinase anchoring proteins that organize PKA and its signalosomes within specific subcellular compartments. Previously, it was found that the absence of A-kinase anchoring protein 3 (AKAP3) leads to multiple morphological abnormalities in mouse sperm. But how AKAP3 regulates sperm motility is yet to be elucidated. AKAP3 has two amphipathic domains, here named dual and RI, in its N-terminus. These domains are responsible for binding regulatory subunits I alpha (RIα) and II alpha (RIIα) of PKA and for RIα only, respectively. Here, we generated mutant mice lacking the dual and RI domains of AKAP3. It was found that the deletion of these domains caused male mouse infertile, accompanied by mild defects in the fibrous sheath of sperm tails. Additionally, the levels of serine/threonine phosphorylation of PKA substrates and tyrosine phosphorylation decreased in the mutant sperm, which exhibited a defect in hyperactivation under capacitation conditions. The protein levels of PKA subunits remained unchanged. But, interestingly, the regulatory subunit RIα was mis-localized from principal piece to midpiece of sperm tail, whereas this was not observed for RIIα. Further protein-protein interaction assays revealed a preference for AKAP3 to bind RIα over RIIα. Collectively, our findings suggest that AKAP3 is important for sperm hyperactivity by regulating type-I PKA signaling pathway mediated protein phosphorylation via its dual and RI domains.


Asunto(s)
Proteínas de Anclaje a la Quinasa A , Proteína Quinasa Tipo I Dependiente de AMP Cíclico , Motilidad Espermática , Animales , Masculino , Ratones , Proteínas de Anclaje a la Quinasa A/genética , Proteínas de Anclaje a la Quinasa A/metabolismo , Proteína Quinasa Tipo I Dependiente de AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Fertilidad/genética , Semen/metabolismo , Transducción de Señal/fisiología , Motilidad Espermática/genética , Espermatozoides/metabolismo , Capacitación Espermática/genética
5.
New Phytol ; 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509454

RESUMEN

Gene expression is regulated at multiple levels, including RNA processing and DNA methylation/demethylation. How these regulations are controlled remains unclear. Here, through analysis of a suppressor for the OsEIN2 over-expressor, we identified an RNA recognition motif protein SUPPRESSOR OF EIN2 (SOE). SOE is localized in nuclear speckles and interacts with several components of the spliceosome. We find SOE associates with hundreds of targets and directly binds to a DNA glycosylase gene DNG701 pre-mRNA for efficient splicing and stabilization, allowing for subsequent DNG701-mediated DNA demethylation of the transgene promoter for proper gene expression. The V81M substitution in the suppressor mutant protein mSOE impaired its protein stability and binding activity to DNG701 pre-mRNA, leading to transgene silencing. SOE mutation enhances grain size and yield. Haplotype analysis in c. 3000 rice accessions reveals that the haplotype 1 (Hap 1) promoter is associated with high 1000-grain weight, and most of the japonica accessions, but not indica ones, have the Hap 1 elite allele. Our study discovers a novel mechanism for the regulation of gene expression and provides an elite allele for the promotion of yield potentials in rice.

6.
Exp Cell Res ; 425(2): 113543, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36894050

RESUMEN

Hypoxia was proved to enhance the angiogenesis of stem cells. However, the mechanism of the angiogenic potential in hypoxia-pretreated dental pulp stem cells (DPSCs) is poorly understood. We previously confirmed that hypoxia enhances the angiogenic potential of DPSC-derived exosomes with upregulation of lysyl oxidase-like 2 (LOXL2). Therefore, our study aimed to illuminate whether these exosomes promote angiogenesis via transfer of LOXL2. Exosomes were generated from hypoxia-pretreated DPSCs (Hypo-Exos) stably silencing LOXL2 after lentiviral transfection and characterized with transmission electron microscopy, nanosight and Western blot. The efficiency of silencing was verified using quantitative real-time PCR (qRT-PCR) and Western blot. CCK-8, scratch and transwell assays were conducted to explore the effects of LOXL2 silencing on DPSCs proliferation and migration. Human umbilical vein endothelial cells (HUVECs) were co-incubated with exosomes to assess the migration and angiogenic capacity through transwell and matrigel tube formation assays. The relative expression of angiogenesis-associated genes was characterized by qRT-PCR and Western blot. LOXL2 was successfully silenced in DPSCs and inhibited DPSC proliferation and migration. LOXL2 silencing in Hypo-Exos partially reduced promotion of HUVEC migration and tube formation and inhibited the expression of angiogenesis-associated genes. Thus, LOXL2 is one of various factors mediating the angiogenic effects of Hypo-Exos.


Asunto(s)
Exosomas , Humanos , Exosomas/metabolismo , Proliferación Celular/genética , Neovascularización Fisiológica/genética , Células Endoteliales de la Vena Umbilical Humana , Células Madre , Aminoácido Oxidorreductasas/genética
7.
Int Endod J ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713190

RESUMEN

AIM: Endothelial cells (EDs) play a key role in angiogenesis and are associated with granulomatous lesions in patients with chronic apical periodontitis (CAP). This study aimed to investigate the diversity of EDs using single-cell ribonucleic acid sequencing (scRNA-seq) and to evaluate the regulation of intercellular adhesion molecule 1 (ICAM1) on the ferroptosis-related protein, prostaglandin-endoperoxide synthase 2 (PTGS2), in CAP. METHODOLOGY: EDs from the uploaded scRNA-seq data of five CAP samples (GSE181688 and GSE197680) were categorized using distinct marker genes. The interactions between vein EDs (veinEndo) and other cell types were analysed using CellPhoneDB. Differentially expressed proteins in the proteomics of human umbilical vein EDs (HUVECs) and THP-1-derived macrophages infected with Porphyromonas gingivalis were compared with the differentially expressed genes (DEGs) of VeinEndo in scRNA-seq of CAP versus healthy control periodontal tissues. The protein-protein interaction of ICAM1-PTGS2 in macrophages and HUVECs was validated by adding recombinant ICAM1, ICAM1 inhibitor and PTGS2 inhibitor using real-time polymerase chain reaction (PCR), western blotting, and immunofluorescence staining. RESULTS: EDs in patients with CAP were divided into eight subclusters: five vein ED, capillaries, arterials and EC (PLA). There were 29 mutually upregulated DEGs and two mutually downregulated DEGs in vein cells in the scRNA-seq data, as well as differentially expressed proteins in the proteomics of HUVECs. Real-time PCR and immunofluorescence staining showed that ICAM1 and PTGS2 were highly expressed in CAP, infected HUVECs, and macrophages. Recombinant protein ICAM1 may improve PTGS2 expression, reactive oxygen species (ROS), and Fe2+ levels and decrease glutathione peroxidase 4 (GPX4) and SLC7A11 protein levels. ICAM1 inhibitor may inverse the above changes. CONCLUSIONS: scRNA-seq revealed the diversity of EDs in CAP and identified the possible regulation of ICAM1 by the ferroptosis-related protein, PTGS2, in infected HUVECs and macrophages, thus providing a basis for therapeutic approaches that target the inflammatory microenvironment of CAP.

8.
Int J Cancer ; 152(11): 2338-2350, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36631999

RESUMEN

Pulmonary lymphoepithelioma-like carcinoma (PLELC) is a rare and histologically distinctive subtype of nonsmall cell lung cancer (NSCLC). High expression of programmed death ligand 1 (PD-L1) and scarcity of druggable driver mutations raise the potential of immunotherapy for advanced PELEC. However, evidence on the clinical impact of immune-checkpoint inhibitors (ICIs) remained limited and unconvincing. The present study retrospectively enrolled advanced PLELC patients who received ICIs either as up-front or salvage therapy in SYSUCC between March 15, 2017 and March 15, 2022. The comparative efficacy of chemoimmunotherapy vs chemotherapy in the first-line setting and chemoimmunotherapy vs ICIs monotherapy in the ≥2 line setting was investigated. A total of 96 patients were finally enrolled; 49 PLELC patients received immunotherapy plus platinum-based chemotherapy, while 45 patients received platinum-based chemotherapy as first-line treatment. Patients with chemoimmunotherapy significantly obtain more survival benefits than those receiving chemotherapy (median progression-free survival [PFS]: 15.6 vs 8.6 months, P = .0015). Additionally, patients with chemoimmunotherapy obtained more PFS benefits than those with ICIs monotherapy in the ≥2 line of therapy (median PFS: 21.7 months vs 7.8 months, P = .094). A significant correlation was observed between prognostic nutritional index (PNI) and favorable treatment outcomes in patients receiving first-line chemoimmunotherapy (median PFS: 17.8 months vs 7.6 months, P < .0001). Likewise, patients in the monocyte-to-lymphocyte ratio (MLR)-high group had significantly shorter PFS than the MLR-low group (median PFS: 11.2 months vs not reached, P = .0009). Our study elucidated the superior efficacy of ICIs therapy, especially chemoimmunotherapy in advanced PLELC, which may provide new insight into the role of immunotherapy in advanced PLELC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Estudios Retrospectivos , Neoplasias Pulmonares/tratamiento farmacológico , Inmunoterapia
9.
Plant Cell Environ ; 46(4): 1060-1074, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36397123

RESUMEN

Rice is an important food crop in the world and the study of its growth and plasticity has a profound influence on sustainable development. Ethylene modulates multiple agronomic traits of rice as well as abiotic and biotic stresses during its lifecycle. It has diverse roles, depending on the organs, developmental stages and environmental conditions. Compared to Arabidopsis (Arabidopsis thaliana), rice ethylene signalling pathway has its own unique features due to its special semiaquatic living environment and distinct plant structure. Ethylene signalling and responses are part of an intricate network in crosstalk with internal and external factors. This review will summarize the current progress in the mechanisms of ethylene-regulated coleoptile growth in rice, with a special focus on ethylene signaling and interaction with other hormones. Insights into these molecular mechanisms may shed light on ethylene biology and should be beneficial for the genetic improvement of rice and other crops.


Asunto(s)
Arabidopsis , Oryza , Reguladores del Crecimiento de las Plantas/metabolismo , Plantones/metabolismo , Oryza/genética , Cotiledón/metabolismo , Etilenos/metabolismo , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas
10.
BMC Cancer ; 23(1): 72, 2023 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-36670414

RESUMEN

BACKGROUND & OBJECTIVE: "Anti-angiogenetic drugs plus chemotherapy" (anti-angio-chemo) and "immune checkpoint inhibitors plus chemotherapy" (ICI-chemo) are superior to traditional chemotherapy in the first-line treatment of patients with advanced non-small-cell lung cancer (NSCLC). However, in the absence of a direct comparison of ICI-chemo with anti-angio-chemo, the superior one between them has not been decided, and the benefit of adding anti-angiogenetic agents to ICI-chemo remains controversial. This study aimed to investigate the role of antiangiogenic agents for advanced NSCLC in the era of immunotherapy. METHODS: Eligible randomized controlled trials (RCTs) comparing chemotherapy versus therapeutic regimens involving ICIs or anti-angiogenetic drugs were included. Outcomes included progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and rate of grade 3-4 toxicity assessment. R-4.3.1 was utilized to perform the analysis. RESULTS: A total of 54 studies with a sample size of 25,046 were finally enrolled. "Atezolizumab + Bevacizumab + Chemotherapy" significantly improved the ORR compared with "Atezolizumab + Chemotherapy" (Odds ratio (OR) = 2.73, 95% confidence interval (CI): 1.27-5.87). The trend also favored "Atezolizumab + Bevacizumab + Chemotherapy" in PFS and OS (hazard ratio (HR) = 0.71, 95% CI: 0.39-1.31; HR = 0.94, 95% CI: 0.77-1.16, respectively). In addition, "Pembrolizumab + Chemotherapy" and "Camrelizumab + Chemotherapy" significantly prolonged the PFS compared to "Bevacizumab + Chemotherapy" (HR = 0.65, 95% CI: 0.46-0.92; HR = 0.63, 95% CI: 0.41-0.97; respectively). Meanwhile, "Pembrolizumab + Chemotherapy" and "Sintilimab + Chemotherapy" yielded more OS benefits than "Bevacizumab + Chemotherapy" (HR = 0.69, 95% CI: 0.56-0.83; HR = 0.64, 95%CI: 0.46-0.91; respectively). Scheme between "Atezolizumab + Bevacizumab + Chemotherapy" and "Atezolizumab + Chemotherapy" made no significant difference (OR = 1.18, 95%CI: 0.56-2.42) concerning the rate of grade 3-4 toxicity. It seemed that ICI-chemo yielded more improvement in quality-adjusted life-year (QALY) than "Bevacizumab + Chemotherapy" in cost-effectiveness analysis. CONCLUSION: Our results suggest that ICI-chemo is associated with potentially longer survival, better cost-effectiveness outcomes, and comparable safety profiles than anti-angio-chemo. Also, adding bevacizumab to ICI-chemo seemed to provide additional therapeutic benefits without adding treatment burden. Our findings would supplement the current standard of care and help the design of future clinical trials for the first-line treatment of patients with advanced NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Inhibidores de la Angiogénesis/efectos adversos , Bevacizumab/uso terapéutico , Inmunoterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
11.
PLoS Biol ; 18(6): e3000748, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32559189

RESUMEN

Curli play critical roles in biofilm formation, host cell adhesion, and colonization of inert surfaces in many Enterobacteriaceae. In Escherichia coli, curli biogenesis requires 7 curli-specific gene (csg) products-CsgA through G-working in concert. Of them, CsgG and CsgF are 2 outer membrane (OM)-localized components that consists of the core apparatus for secretion and assembly of curli structural subunits, CsgB and CsgA. Here, we report the cryogenic electron microscopy (cryo-EM) structure of CsgG in complex with CsgF from E. coli. The structure reveals that CsgF forms a stable complex with CsgG via a 1:1 stoichiometry by lining the upper lumen of the nonameric CsgG channel via its N-terminal 27 residues, forming a funnel-like entity plugged in the CsgG channel and creating a unique secretion channel with 2 constriction regions, consistent with the recently reported structure of the CsgG-CsgF complex. Functional studies indicate that export of CsgF to the cell surface requires the CsgG channel, and CsgF not only functions as an adaptor that bridges CsgB with CsgG but also may play important roles in controlling the rates of translocation and/or polymerization for curli structural subunits. Importantly, we found that a series of CsgF-derived peptides are able to efficiently inhibit curli production to E. coli when administrated exogenously, highlighting a potential strategy to interfere biofilm formation in E. coli strains.


Asunto(s)
Amiloide/ultraestructura , Microscopía por Crioelectrón , Proteínas de Escherichia coli/ultraestructura , Escherichia coli/metabolismo , Escherichia coli/ultraestructura , Complejos Multiproteicos/ultraestructura , Multimerización de Proteína , Secuencia de Aminoácidos , Análisis Mutacional de ADN , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Modelos Moleculares , Péptidos/química , Péptidos/metabolismo , Unión Proteica
12.
Environ Res ; 229: 115980, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37098386

RESUMEN

Accelerated urbanization and industrialization have led to an alarming increase in the generation of wastewater with complex chemical contents. Industrial wastewaters are often a primary source of water contamination. The chemical characterization of different industrial wastewater types is an essential task to interpret the chemical fingerprints of wastewater to identify pollution sources and develop efficient water treatment strategies. In this study, we conduct a non-target chemical analysis for the source characterization of different industrial wastewater samples collected from a chemical industrial park (CIP) located in southeast China. The chemical screening identified volatile and semi-volatile organic compounds that included dibutyl phthalate at a maximum concentration of 13.4 µg/L and phthalic anhydride at 35.9 µg/L. Persistent, mobile, and toxic (PMT) substances among the detected organic compounds were identified and prioritized as high-concern contaminants given their impact on drinking water resources. Moreover, a source analysis of the wastewater collected from the wastewater outlet station indicated that the dye production industry contributed the largest quantities of toxic contaminates (62.6%), and this result was consistent with the ordinary least squares and heatmap results. Thus, our study utilized a combined approach of a non-target chemical analysis, a pollution source identification method, and a PMT assessment of different industrial wastewater samples collected from the CIP. The results of the chemical fingerprints of different industrial wastewater types as well as the results of the PMT assessment benefit risk-based wastewater management and source reduction strategies.


Asunto(s)
Contaminantes Ambientales , Compuestos Orgánicos Volátiles , Contaminantes Químicos del Agua , Contaminantes Ambientales/análisis , Aguas Residuales , Contaminantes Químicos del Agua/análisis , China
13.
Cancer ; 128(21): 3804-3814, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36069292

RESUMEN

BACKGROUND: Afatinib is the only currently approved EGFR-tyrosine kinase inhibitors for advanced non-small cell lung cancer (NSCLC) patients with EGFR G719X/L861Q/S768I. However, there are limited real-world data concerning the benefits and resistance mechanisms of afatinib in patients with these nonclassical mutations. To fill this gap, the present study was conducted. METHODS: All NSCLC patients treated with afatinib were screened, and patients with EGFR G719X/L861Q/S768I were enrolled into the analysis. Either tumor tissue or blood specimens were detected by the commercial next-generation sequencing (NGS) panels or amplification-refractory mutation system (ARMS)-polymerase chain reaction (PCR) to figure out the mutation genotype. RESULTS: A total of 106 advanced NSCLC patients with EGFR G719X/L861Q/S768I received afatinib treatment. The benefits of afatinib exhibited heterogeneity in different mutation genotypes. Notably, at baseline, NGS testing was performed in 59 patients, and TP53 was the most frequently coexisting mutation. Patients with TP53 mutations obtained fewer survival benefits than those with TP53 wild-type. A total of 68 patients ultimately experienced progression, and 27 patients received NGS testing to clarify the potential resistance mechanisms. EGFR-T790M, CDK4 amplification, FGFR1 amplification, PIK3CA, MET amplification, RET fusions, HER2, and BRAF mutations were identified in three (11.1%), three (11.1%), three (11.1%), three (11.1%), three (11.1%), one (3.7%), one (3.7%), and one (3.7%) of the cases, respectively. Five patients underwent ARMS-PCR testing for detecting EGFR-T790M mutation, and only one patient was T790M-positive. CONCLUSIONS: The present study elucidated the differential benefits of afatinib within different mutation genotypes and first revealed the spectrum of potential resistance mechanisms in patients with EGFR G719X/L861Q/S768I. The results of this study may provide practical clinical information that can guide optimal treatment in this setting.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Afatinib/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Fosfatidilinositol 3-Quinasa Clase I/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas B-raf/genética
14.
FASEB J ; 35(1): e21207, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33368572

RESUMEN

ß-barrel outer membrane proteins (ß-OMPs) play critical roles in nutrition acquisition, protein import/export, and other fundamental biological processes. The assembly of ß-OMPs in Gram-negative bacteria is mediated by the ß-barrel assembly machinery (BAM) complex, yet its precise mechanism remains elusive. Here, we report two structures of the BAM complex in detergents and in nanodisks, and two crystal structures of the BAM complex with bound substrates. Structural analysis indicates that the membrane compositions surrounding the BAM complex could modulate its overall conformations, indicating low energy barriers between different conformational states and a highly dynamic nature of the BAM complex. Importantly, structures of the BAM complex with bound substrates and the related functional analysis show that the first ß-strand of the BamA ß-barrel (ß1BamA ) in the BAM complex is associated with the last but not the first ß-strand of a ß-OMP substrate via antiparallel ß-strand interactions. These observations are consistent with the ß-signal hypothesis during ß-OMP biogenesis, and suggest that the ß1BamA strand in the BAM complex may interact with the last ß-strand of an incoming ß-OMP substrate upon their release from the chaperone-bound state.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/química , Aprendizaje Automático , Conformación Proteica en Lámina beta , Dominios Proteicos
15.
Mol Cell Biochem ; 477(12): 2871-2881, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35699827

RESUMEN

The aim of this study is to investigate the role of calcium-sensing receptor (CaSR) in the expression of inflammatory mediators of lipopolysaccharide (LPS)-treated human dental pulp cells (hDPCs). The expression profile of CaSR in LPS-simulated hDPCs was detected using immunofluorescence, real time quantitative PCR (RT-qPCR), and Western blot analyses. Then, its regulatory effects on the expression of specific inflammatory mediators such as interleukin (IL)-1ß, IL-6, cyclooxygenase 2 (COX2)-derived prostaglandin E2 (PGE2), tumor necrosis factor (TNF)-α, and IL-10 were determined by RT-qPCR and enzyme-linked immunosorbent assay (ELISA). LPS significantly downregulated the gene expression of CaSR, but upregulated its protein expression level in hDPCs. Treatments by CaSR agonist R568 or its antagonist Calhex231, and their combinations with protein kinase B (AKT) inhibitor LY294002 showed obvious effects on the expression of selected inflammatory mediators in a time-dependent manner. Meanwhile, an opposite direction was found between the action of R568 and Calhex231, as well as the expression of the pro- (IL-1ß, IL-6, COX2-derived PGE2, and TNF-α) and anti-inflammatory (IL-10) mediators. The results provide the first evidence that CaSR-phosphatidylinositol-3 kinase (PI3K)-AKT-signaling pathway is involved in the release of inflammatory mediators in LPS-treated hDPCs, suggesting that the activation or blockade of CaSR may provide a novel therapeutic strategy for the treatment of pulp inflammatory diseases.


Asunto(s)
Pulpa Dental , Mediadores de Inflamación , Receptores Sensibles al Calcio , Humanos , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Pulpa Dental/citología , Pulpa Dental/metabolismo , Mediadores de Inflamación/metabolismo , Interleucina-10 , Interleucina-6 , Lipopolisacáridos , FN-kappa B/metabolismo , Prostaglandinas E , Proteínas Proto-Oncogénicas c-akt , Receptores Sensibles al Calcio/genética , Receptores Sensibles al Calcio/metabolismo , Factor de Necrosis Tumoral alfa
16.
Connect Tissue Res ; 63(5): 485-497, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35125056

RESUMEN

AIM: The aim of this study was to investigate the influence of pigment epithelium-derived factor (PEDF) on periodontal homeostasis in mice and the osteogenic differentiation of human periodontal ligament fibroblasts (PDLFs). MATERIALS AND METHODS: Micro-computed tomography and histology were performed to compare the alveolar bone volume, density, and bone-related markers between PEDF-deficient (PEDF-/-) and wild-type (WT) mice. Furthermore, after recombinant human PEDF treatment, the PDLF viability and osteogenic differentiation were examined using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay, alkaline phosphatase (ALP) activity assay, Von Kossa staining, Alizarin red staining, real-time quantitative polymerase chain reaction (qRT-PCR), and immunoblotting. RESULTS: The alveolar bone volume and density of PEDF-/- mice were significantly lower than those of the WT mice. Higher receptor activator for nuclear factor-κB ligand (RANKL) expression and lower osteoprotegerin (OPG) expression levels were observed in the PEDF-/- group. Moreover, PEDF treatment did not affect the PDLF proliferation. PEDF dose-dependently improved mineral deposition. Compared with the control group, 250 ng/mL PEDF promoted OPG mRNA expression in PDLFs on Day 3 but inhibited RANKL, Wnt5a, GSK3b mRNA, and non-phosphorylated ß-catenin protein expression. However, 250 ng/mL PEDF had no significant effect on the expression of Wnt3a. On Day 7, after culture with 250 ng/mL PEDF in osteogenic medium, the ALP and RUNX2 protein levels were upregulated. VEGF protein expression was reduced in a dose-dependent manner after PEDF stimulation. The PEDF protein expression increased as the osteogenic induction time increased. CONCLUSION: PEDF gene knockout suppresses periodontal homeostasis in mice, and PEDF treatment induces PDLF osteogenic differentiation in vitro.


Asunto(s)
Fibroblastos , Factores de Crecimiento Nervioso , Osteogénesis , Ligamento Periodontal , Serpinas , Fosfatasa Alcalina/metabolismo , Animales , Diferenciación Celular , Células Cultivadas , Proteínas del Ojo , Fibroblastos/citología , Homeostasis , Humanos , Ratones , Ratones Noqueados , Factores de Crecimiento Nervioso/metabolismo , Ligamento Periodontal/citología , ARN Mensajero/metabolismo , Serpinas/metabolismo , Microtomografía por Rayos X
17.
Cancer Control ; 29: 10732748221081360, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35201951

RESUMEN

OBJECTIVES: Osimertinib has exhibited promising central nervous system (CNS) efficacy in Epidermal growth factor receptor (EGFR)-mutated advanced non-small-cell lung cancer (NSCLC) patients. In real-world clinical practice, patients would turn to plasma genotyping or take osimertinib blindly after CNS progression on previous tyrosine kinase inhibitors (TKIs). However, the efficacy of osimertinib in those patients according to their T790M mutational status has not been explored. MATERIALS AND METHODS: Twenty-five patients who received osimertinib due to intracranial progressions with stable extracranial diseases after early-generation EGFR-TKI treatment were collected from 1032 EGFR-mutated NSCLC. Plasma samples were analyzed for EGFR mutations using next-generation sequencing (NGS) or polymerase chain reaction (PCR). RESULTS: Among the 25 patients, 17 patients took plasma genotyping before osimertinib treatment with 8 patients EGFR T790M mutation-positive and the rest started osimertinib blindly. The median progression-free survival (PFS) was 8.0 months (95% confidence interval [CI]: 6.12-9.94) and median intracranial PFS (iPFS) was 14.4 months (95% CI: 7.27-21.59) for the total population. No statistical difference was found in PFS and iPFS among patients with different EGFR T790M mutational statuses. Intracranial disease control rate (DCR) was 100.0% for 14 patients with evaluable intracranial lesions despite different T790M mutational statuses. DCR for extracranial lesions and overall lesions were 100.0%, 66.7%, and 87.5% for patients with T790M, no T790M, and unknown T790M mutational status, respectively. CONCLUSION: For EGFR-mutated NSCLC patients with only intracranial progressions after previous TKI treatments, osimertinib is a promising treatment option regardless of T790M mutational status from plasma genotyping.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Acrilamidas , Compuestos de Anilina , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Mutación , Inhibidores de Proteínas Quinasas/uso terapéutico
18.
Sensors (Basel) ; 22(18)2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-36146131

RESUMEN

This study aims to reveal the buckling behavior of filament-wound composite cylindrical shells subjected to external pressure. The boundary conditions of the cylindrical shells were one end fixed and the other free. The carbon fiber stacking sequences were [±90]2/([±20]/[±90]/[±40]/[±90]/[±60]/[±90])2/[±90]. Finite element software ANSYS 16.2 was used for the numerical simulation to predict the critical buckling pressure and buckling behavior of composite cylindrical shell. External hydrostatic pressure tests were conducted, where the buckling behavior and strain response were observed. Numerical simulation accurately predicted the critical buckling pressure of carbon fiber/epoxy filament composite cylindrical shells under external pressure with 3.5% deviation from the experimental results. The buckling modes simulated by the finite element method agreed well with the deformed shape observed in the experiment, which was characterized by the uniform distribution of the three hoop waves. Comparing the axial compressive strain and hoop compressive strain of the composite shell, it was found that the circumferential stiffness of the shell was weaker than the axial stiffness. In addition, a comparative study of the strains of the fixed-end and free-end metal control sleeves was carried out. The results show that the boundary conditions have a significant influence on the strain response of control sleeves.

19.
Proc Natl Acad Sci U S A ; 115(10): 2520-2525, 2018 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-29463697

RESUMEN

The phytohormone ethylene regulates many aspects of plant growth and development. EIN2 is the central regulator of ethylene signaling, and its turnover is crucial for triggering ethylene responses. Here, we identified a stabilizer of OsEIN2 through analysis of the rice ethylene-response mutant mhz3. Loss-of-function mutations lead to ethylene insensitivity in etiolated rice seedlings. MHZ3 encodes a previously uncharacterized membrane protein localized to the endoplasmic reticulum. Ethylene induces MHZ3 gene and protein expression. Genetically, MHZ3 acts at the OsEIN2 level in the signaling pathway. MHZ3 physically interacts with OsEIN2, and both the N- and C-termini of MHZ3 specifically associate with the OsEIN2 Nramp-like domain. Loss of mhz3 function reduces OsEIN2 abundance and attenuates ethylene-induced OsEIN2 accumulation, whereas MHZ3 overexpression elevates the abundance of both wild-type and mutated OsEIN2 proteins, suggesting that MHZ3 is required for proper accumulation of OsEIN2 protein. The association of MHZ3 with the Nramp-like domain is crucial for OsEIN2 accumulation, demonstrating the significance of the OsEIN2 transmembrane domains in ethylene signaling. Moreover, MHZ3 negatively modulates OsEIN2 ubiquitination, protecting OsEIN2 from proteasome-mediated degradation. Together, these results suggest that ethylene-induced MHZ3 stabilizes OsEIN2 likely by binding to its Nramp-like domain and impeding protein ubiquitination to facilitate ethylene signal transduction. Our findings provide insight into the mechanisms of ethylene signaling.


Asunto(s)
Proteínas de la Membrana/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Etilenos/metabolismo , Etiolado , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Mutación , Oryza/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/genética , Dominios Proteicos , Plantones/genética , Plantones/metabolismo , Transducción de Señal/genética , Transducción de Señal/fisiología
20.
J Cell Biochem ; 121(8-9): 3825-3836, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31692088

RESUMEN

Brown adipocytes are rich in mitochondria and linked to the body's blood fat levels and obesity. MiR-92a is negatively correlated with the activity of brown adipocytes. This study aimed to explore the mechanism of miR-92a on brown adipocytes. The expression of miR-92a in C2C12 cell was detected by a quantitative real-time-polymerase chain reaction (qRT-PCR). C2C12 cells were induced to brown adipocytes. The direct target gene of miR-92a was determined using the dual-luciferase reporter assay. Brown adipocytes were treated with isoprenaline (Iso) and transfected by miR-92a inhibitor and siSMAD7. The expression of heat-producing genes and adipose differentiation genes related to brown adipocytes were detected by qRT-PCR and Western blot analysis. The expression of SMAD7, p-SMAD2, and p-SMAD3 were detected using Western blot analysis. The mitochondrial content was measured by mitotracker fluorescent staining. MiR-92a inhibitor significantly decreased the expression of miR-92a in C2C12 cells. MiR-92a inhibitor could upregulate the expression of Ucp1, Cox7a1, Elovl3, Ppargc1α, PPARγ, and FABP4, and its effect on Ucp1 was increased after the treatment of isoprenaline. Moreover, miR-92a inhibitor increased mitochondrial content, oxygen consumption rate (OCR) and the expression of SMAD7 and suppressed the expressions of p-SMAD2 and p-SMAD3, whereas miR-92a directly targeted SMAD7 to exert its inhibitory effects. SiSMAD7 reversed the effects of the inhibitor on heat-producing genes, mitochondrial content, OCR and the expressions of SMAD7, p-SMAD2, and p-SMAD3 in brown adipocytes. Blocking miR-92a might promote brown adipocytes differentiation, mitochondrial oxidative respiration, and thermogenesis by targeting SMAD7 to inhibit the expressions of p-SMAD2 and p-SMAD3.

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