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1.
J Immunother Cancer ; 12(7)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38964787

RESUMO

BACKGROUND: Chimeric antigen receptor natural killer (CAR-NK) therapy holds great promise for treating hematologic tumors, but its efficacy in solid tumors is limited owing to the lack of suitable targets and poor infiltration of engineered NK cells. Here, we explore whether immunogenic cell death (ICD) marker ERp57 translocated from endoplasmic reticulum to cell surface after drug treatment could be used as a target for CAR-NK therapy. METHODS: To target ERp57, a VHH phage display library was used for screening ERp57-targeted nanobodies (Nbs). A candidate Nb with high binding affinity to both human and mouse ERp57 was used for constructing CAR-NK cells. Various in vitro and in vivo studies were performed to assess the antitumor efficacy of the constructed CAR-NK cells. RESULTS: We demonstrate that the translocation of ERp57 can not only be induced by low-dose oxaliplatin (OXP) treatment but also is spontaneously expressed on the surface of various types of tumor cell lines. Our results show that G6-CAR-NK92 cells can effectively kill various tumor cell lines in vitro on which ERp57 is induced or intrinsically expressed, and also exhibit potent antitumor effects in cancer cell-derived xenograft and patient-derived xenograft mouse models. Additionally, the antitumor activity of G6-CAR-NK92 cells is synergistically enhanced by the low-dose ICD-inducible drug OXP. CONCLUSION: Collectively, our findings suggest that ERp57 can be leveraged as a new tumor antigen for CAR-NK targeting, and the resultant CAR-NK cells have the potential to be applied as a broad-spectrum immune cell therapy for various cancers by combining with ICD inducer drugs.


Assuntos
Morte Celular Imunogênica , Células Matadoras Naturais , Oxaliplatina , Isomerases de Dissulfetos de Proteínas , Humanos , Animais , Camundongos , Oxaliplatina/farmacologia , Oxaliplatina/uso terapêutico , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Morte Celular Imunogênica/efeitos dos fármacos , Isomerases de Dissulfetos de Proteínas/metabolismo , Imunoterapia Adotiva/métodos , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Neoplasias/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Feminino
2.
Biomater Res ; 28: 0041, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38911825

RESUMO

Surgery and targeted therapy are of equal importance for colorectal cancer (CRC) treatment. However, complete CRC tumor resection remains challenging, and new targeted agents are also needed for efficient CRC treatment. Cadherin 17 (CDH17) is a membrane protein that is highly expressed in CRC and, therefore, is an ideal target for imaging-guided surgery and therapeutics. This study utilizes CDH17 nanobody (E8-Nb) with the near-infrared (NIR) fluorescent dye IRDye800CW to construct a NIR-II fluorescent probe, E8-Nb-IR800CW, and a Pseudomonas exotoxin (PE)-based immunotoxin, E8-Nb-PE38, to evaluate their performance for CRC imaging, imaging-guided precise tumor excision, and antitumor effects. Our results show that E8-Nb-IR800CW efficiently recognizes CDH17 in CRC cells and tumor tissues, produces high-quality NIR-II images for CRC tumors, and enables precise tumor removal guided by NIR-II imaging. Additionally, fluorescent imaging confirms the targeting ability and specificity of the immunotoxin toward CDH17-positive tumors, providing the direct visible evidence for immunotoxin therapy. E8-Nb-PE38 immunotoxin markedly delays the growth of CRC through the induction of apoptosis and immunogenic cell death (ICD) in multiple CRC tumor models. Furthermore, E8-Nb-PE38 combined with 5-FU exerts synergistically antitumor effects and extends survival. This study highlights CDH17 as a promising target for CRC imaging, imaging-guided surgery, and drug delivery. Nanobodies targeting CDH17 hold great potential to construct NIR-II fluorescent probes for surgery navigation, and PE-based toxins fused with CDH17 nanobodies represent a novel therapeutic strategy for CRC treatment. Further investigation is warranted to validate these findings for potential clinical translation.

3.
Exp Biol Med (Maywood) ; 249: 10057, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562529

RESUMO

Tinnitus is a disturbing condition defined as the occurrence of acoustic hallucinations with no actual sound. Although the mechanisms underlying tinnitus have been explored extensively, the pathophysiology of the disease is not completely understood. Moreover, genes and potential treatment targets related to auditory hallucinations remain unknown. In this study, we examined transcriptional-profile changes in the medial geniculate body after noise-induced tinnitus in rats by performing RNA sequencing and validated differentially expressed genes via quantitative polymerase chain reaction analysis. The rat model of tinnitus was established by analyzing startle behavior based on gap-pre-pulse inhibition of acoustic startles. We identified 87 differently expressed genes, of which 40 were upregulated and 47 were downregulated. Pathway-enrichment analysis revealed that the differentially enriched genes in the tinnitus group were associated with pathway terms, such as coronavirus disease COVID-19, neuroactive ligand-receptor interaction. Protein-protein-interaction networks were established, and two hub genes (Rpl7a and AC136661.1) were identified among the selected genes. Further studies focusing on targeting and modulating these genes are required for developing potential treatments for noise-induced tinnitus in patients.


Assuntos
Zumbido , Humanos , Ratos , Animais , Zumbido/genética , Zumbido/metabolismo , Corpos Geniculados/metabolismo , Ruído/efeitos adversos
4.
Am J Audiol ; 33(2): 433-441, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38661487

RESUMO

PURPOSE: So far, there have been no in-depth analyses of the connection between tinnitus sensation-level loudness and sleep quality. Accordingly, the present study was formulated as a mediation analysis focused on exploring this relationship. METHOD: Overall, 1,255 adults with consecutive subjective tinnitus who had sought outpatient treatment were enrolled in the present study. RESULTS: Direct effects of tinnitus sensation-level loudness on sleep quality were not statistically significant (95% confidence intervals [CI] include zero), as measured by the point estimate, -0.016. However, the 95% CI for indirect effects did not include zero when assessing the Self-Rating Anxiety Scale (SAS) scores, the Self-Rating Depression Scale (SDS) scores, the visual analogue scale (VAS) scores, and self-reported tinnitus annoyance. CONCLUSIONS: These results suggest that tinnitus sensation-level loudness does not directly have an effect on sleep quality. However, it indirectly impacts sleep quality, mediated by SAS scores, SDS scores, the impact of tinnitus on life measured using the VAS, and self-reported tinnitus annoyance. As such, alleviating anxiety and depression in patients with tinnitus may result in reductions in their insomnia even if there is no reduction in tinnitus loudness. Importantly, otolaryngologists and other clinicians treating tinnitus should refer patients with tinnitus suffering from insomnia with comorbid depression or anxiety for appropriate psychological and/or psychiatric treatment.


Assuntos
Ansiedade , Depressão , Percepção Sonora , Análise de Mediação , Qualidade do Sono , Zumbido , Humanos , Zumbido/psicologia , Zumbido/fisiopatologia , Zumbido/complicações , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Autorrelato , Distúrbios do Início e da Manutenção do Sono
6.
Bioorg Med Chem Lett ; 99: 129613, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38224754

RESUMO

A series of bis-isatin conjugates with lysine linker were synthesized with the aim of probing their antiproliferative potential. All the newly synthesized derivatives (0-100 µM) were first screened against liver cancer cell lines(Huh1, H22, Huh7, Hepa1-6, HepG2, Huh6 and 97H) using CCK-8 assay. Results indicated that the derivative 4d exhibited the most potent activity against Huh1 (IC50 = 17.13 µM) and Huh7(IC50 = 8.265 µM). In vivo anti-tumor study showed that compound 4d effectively inhibited tumor growth in Huh1-induced xenograft mouse model; the anti-tumor effect of compound 4d (15 mg/kg) was comparable with sorafenib (20 mg/kg). H&E staining analysis and routine blood test and blood serum biochemistry examination was performed to confirm the safety of compound 4d in xenograft models. The mechanism of action of 4d on tumor growth inhibition was further investigated by RNA-Seq analysis, which indicates a positive regulation of autophagy signaling pathway, which was further confirmed with key biomarker expression of autophagy after 4d treatment. Our results suggest that the bis-isatin conjugate compound 4d is a promising tumor inhibitory agent for some liver cancer.


Assuntos
Antineoplásicos , Isatina , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Linhagem Celular Tumoral , Isatina/química , Ensaios de Seleção de Medicamentos Antitumorais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Proliferação de Células , Relação Estrutura-Atividade , Estrutura Molecular
7.
Adv Biol (Weinh) ; 8(2): e2300477, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37867281

RESUMO

In recent years, there has been growing concern over the rising incidence of liver diseases, with increasing exposure to environmental toxins as a significant contributing factor. However, the mechanisms of liver injury induced by environmental pollutants are largely unclear. Here, using tetrabromobisphenol A (TBBPA), a widely used brominated flame retardant, as an example, environmental toxin-induced liver toxicity in mice is characterized via single-cell sequencing technology. Heterogeneous gene expression profiles after exposure to TBBPA in major cell types of the liver are demonstrated. In hepatocytes, pathway analysis of differentially expressed genes reveals the enhanced interferon response and diminished metabolic processes. The disrupted endothelial functions in TBBPA-treated cells are then shown. Moreover, the activation of M2-polarization in Kupffer cells, as well as activated effector T and B cells are unveiled in TBBPA-treated cells. Finally, ligand-receptor pair analysis shows that TBBPA disrupts cell-cell communication and induces an inflammatory microenvironment. Overall, the results reveal that TBBPA-induced dysfunction of hepatocytes and endothelial cells may then activate and recruit other immune cells such as Kuffer cells, and T/NK cells into the liver, further increasing inflammatory response and liver injury. Thus, the results provide novel insight into undesiring environmental pollutant-induced liver injury.


Assuntos
Poluentes Ambientais , Bifenil Polibromatos , Camundongos , Animais , Células Endoteliais , Fígado/metabolismo , Bifenil Polibromatos/toxicidade , Bifenil Polibromatos/metabolismo , Poluentes Ambientais/metabolismo , Análise de Sequência de RNA
8.
J Nanobiotechnology ; 21(1): 442, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37993888

RESUMO

Imaging-guided photothermal therapy (PTT) for cancers recently gathered increasing focus thanks to its precise diagnosis and potent therapeutic effectiveness. Croconaine (CR) dyes demonstrate potential in expanding utility for near infrared (NIR) dyes in bio-imaging/theranostics. However, reports on CR dyes for PTT are scarce most likely due to the short of the efficacious delivery strategies to achieve specific accumulation in diseased tissues to induce PTT. Extracellular vesicles (EVs) are multifunctional nanoparticle systems that function as safe platform for disease theragnostics, which provide potential benefits in extensive biomedical applications. Here, we developed a novel delivery system for photothermal molecules based on a CR dye that exerts photothermal activity through CDH17 nanobody-engineered EVs. The formed CR@E8-EVs showed strong NIR absorption, excellent photothermal performance, good biological compatibility and superb active tumor-targeting capability. The CR@E8-EVs can not only visualize and feature the tumors through CR intrinsic property as a photoacoustic imaging (PAI) agent, but also effectively retard the tumor growth under laser irradiation to perform PTT. It is expected that the engineered EVs will become a novel delivery vehicle of small organic photothermal agents (SOPTAs) in future clinical PTT applications.


Assuntos
Nanopartículas , Neoplasias , Técnicas Fotoacústicas , Humanos , Terapia Fototérmica , Fototerapia/métodos , Nanomedicina Teranóstica/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Corantes , Técnicas Fotoacústicas/métodos , Linhagem Celular Tumoral
9.
J Control Release ; 361: 427-442, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37487929

RESUMO

Due to the unique physicochemical properties, mesoporous silica nanoparticles (MONs) have been widely utilized in biomedical fields for drug delivery, gene therapy, disease diagnosis and imaging. With the extensive applications and large-scale production of MONs, the potential effects of MONs on human health are gaining increased attention. To better understand the cellular and molecular mechanisms underlying the effects of MONs on the mouse liver, we profiled the transcriptome of 63,783 single cells from mouse livers following weekly intravenous administration of MONs for 2 weeks. The results showed that the proportion of endothelial cells and CD4+ T cells was increased, whereas that of Kupffer cells was decreased, in a dose-dependent manner after MONs treatment in the mouse liver. We also observed that the proportion of inflammation-related Kupffer cell subtype and wound healing-related hepatocyte subtype were elevated, but the number of hepatocytes with detoxification characteristics was reduced after MONs treatment. The cell-cell communication network revealed that there was more crosstalk between cholangiocytes and Kupffer cells, liver capsular macrophages, hepatic stellate cells, and endothelial cells following MONs treatment. Furthermore, we identified key ligand-receptor pairs between crucial subtypes after MONs treatment that are known to promote liver fibrosis. Collectively, our study explored the effects of MONs on mouse liver at a single-cell level and provides comprehensive information on the potential hepatotoxicity of MONs.


Assuntos
Células Endoteliais , Nanopartículas , Camundongos , Humanos , Animais , Dióxido de Silício/química , Transcriptoma , Fígado , Hepatócitos , Nanopartículas/química
10.
Future Oncol ; 19(15): 1063-1072, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37283023

RESUMO

Aim: To evaluate independent risk factors specific for early-stage nasopharyngeal carcinoma (NPC). Methods: A total of 566 patients with early-stage NPC from 2004 to 2019 were identified using the Surveillance, Epidemiology and End Results database. Results: Older ages (70-79 and >80 years) were independent risk factors, with hazard ratios of 1.961 and 5.011, respectively. The hazard ratio for early-stage NPC in Asian and Pacific Islander residents (0.475) was lower than that for White residents. A tumor size <3 cm was a protective factor for overall and cancer-specific survival in the current study. Conclusion: In patients with early-stage NPC, age >70 years, race and tumor size were independent prognosticators for cancer-specific survival.


Assuntos
Neoplasias Nasofaríngeas , Humanos , Estados Unidos/epidemiologia , Idoso , Carcinoma Nasofaríngeo/patologia , Prognóstico , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Nasofaríngeas/terapia , Modelos de Riscos Proporcionais , Fatores de Risco , Estadiamento de Neoplasias
11.
Brain Sci ; 13(4)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37190538

RESUMO

Tinnitus is an unpleasant symptom characterized by detective hearing without the actual sound input. Despite numerous studies elucidating a variety of pathomechanisms inducing tinnitus, the pathophysiology of tinnitus is not fully understood. The genes that are closely associated with this subtype of the auditory hallucination that could be utilized as potential treatment targets are still unknown. In this study, we explored the transcriptional profile changes of the auditory cortex after noise-induced tinnitus in rats using high throughput sequencing and verification of the detected genes using quantitative PCR (qPCR). Tinnitus models were established by analyzing startle behaviors through gap pre-pulse inhibition (PPI) of the acoustic startle. Two hundred and fifty-nine differential genes were identified, of which 162 genes were up-regulated and 97 genes were down-regulated. Analysis of the pathway enrichment indicated that the tinnitus group exhibited increased gene expression related to neurodegenerative disorders such as Huntington's disease and Amyotrophic lateral sclerosis. Based on the identified genes, networks of protein-protein interaction were established and five hub genes were identified through degree rank, including Fos, Nr4a1, Nr4a3, Egr2, and Egr3. Therein, the Fos gene ranked first with the highest degree after noise exposure, and may be a potential target for the modulation of noise-induced tinnitus.

12.
Front Neurosci ; 17: 1159019, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37090804

RESUMO

Tinnitus is closely associated with cognition functioning. In order to clarify the central reorganization of tinnitus in patients with vestibular schwannoma (VS), this study explored the aberrant dynamics of electroencephalogram (EEG) microstates and their correlations with tinnitus features in VS patients. Clinical and EEG data were collected from 98 VS patients, including 76 with tinnitus and 22 without tinnitus. Microstates were clustered into four categories. Our EEG microstate analysis revealed that VS patients with tinnitus exhibited an increased frequency of microstate C compared to those without tinnitus. Furthermore, correlation analysis demonstrated that the Tinnitus Handicap Inventory (THI) score was negatively associated with the duration of microstate A and positively associated with the frequency of microstate C. These findings suggest that the time series and syntax characteristics of EEG microstates differ significantly between VS patients with and without tinnitus, potentially reflecting abnormal allocation of neural resources and transition of functional brain activity. Our results provide a foundation for developing diverse treatments for tinnitus in VS patients.

13.
Cancer Commun (Lond) ; 43(3): 338-364, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36602428

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most prevalent cancers in the world, with a high likelihood of metastasis and a dismal prognosis. The reprogramming of glucose metabolism is critical in the development of HCC. The Warburg effect has recently been confirmed to occur in a variety of cancers, including HCC. However, little is known about the molecular biological mechanisms underlying the Warburg effect in HCC cells. In this study, we sought to better understand how methyltransferase 5, N6-adenosine (METTL5) controls the development of HCC and the Warburg effect. METHODS: In the current study, quantitative real-time polymerase chain reaction and Western blotting were used to detect the expression of METTL5 in HCC tissues and cell lines. Several different cell models and animal models were established to determine the role of METTL5 in glucose metabolism reprogramming and the underlying molecular mechanism of HCC. Glutathione-S-transferase pulldown, coimmunoprecipitation, RNA sequencing, non-targeted metabolomics, polysome profiling, and luciferase reporter assays were performed to investigate the molecular mechanisms of METTL5 in HCC cells. RESULTS: We discovered that METTL5 drove glucose metabolic reprogramming to promote the proliferation and metastasis of HCC. Mechanistically, upregulation of METTL5 promoted c-Myc stability and thus activated its downstream glycolytic genes lactate dehydrogenase A (LDHA), enolase 1 (ENO1), triosephosphate isomerase 1 (TPI1), solute carrier family 2 member 1 (SLC2A1), and pyruvate kinase M2 (PKM2). The c-Box and ubiquitin binding domain (UBA) regions of ubiquitin specific peptidase 5 (USP5) binded to c-Myc protein and inhibited K48-linked polyubiquitination of c-Myc. Further study revealed that METTL5 controled the USP5 translation process, which in turn regulated the ubiquitination of c-Myc. Furthermore, we identified cAMP responsive element binding protein 1 (CREB1)/P300 as a critical transcriptional regulator of METTL5 that promoted the transcription of METTL5 in HCC. In patient-derived tumor xenograft (PDX) models, adenovirus-mediated knockout of METTL5 had a good antitumor effect and prolonged the survival of PDX-bearing mice. CONCLUSIONS: These findings point to a novel mechanism by which CREB1/P300-METTL5-USP5-c-Myc controls abnormal glucose metabolism and promotes tumor growth, suggesting that METTL5 is a potential therapeutic target and prognostic biomarker for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Glucose , Neoplasias Hepáticas/patologia , Prognóstico , Proteases Específicas de Ubiquitina
14.
Front Pharmacol ; 13: 1064032, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36569293

RESUMO

Background: Ecto-5'-nucleotidase (NT5E) encodes the cluster of differentiation 73 (CD73), whose overexpression contributes to the formation of immunosuppressive tumor microenvironment and is related to exacerbated prognosis, increased risk of metastasis and resistance to immunotherapy of various tumors. However, the prognostic significance of NT5E in pan-cancer is obscure so far. Methods: We explored the expression level of NT5E in cancers and adjacent tissues and revealed the relationship between the NT5E expression level and clinical outcomes in pan-cancer by utilizing the UCSC Xena database. Then, correlation analyses were performed to evaluate the relationship between NT5E expression and immune infiltration level via EPIC, MCP-counter and CIBERSORT methods, and the enrichment analysis were employed to identify NT5E-interacting molecules and functional pathways. Furthermore, we conducted single-cell analysis to explore the potential role of NT5E on single-cell level based on the CancerSEA database. Meanwhile, gene set enrichment analysis (GSEA) in single-cell level was also conducted in TISCH database and single-cell signature explorer was utilized to evaluate the epithelial-mesenchymal transition (EMT) level in each cell type. Results: The expression level of NT5E was aberrant in almost all cancer types, and was correlated with worse prognosis in several cancers. Notably, NT5E overexpression was related to worse overall survival (OS) in pancreatic adenocarcinoma (PAAD), head and neck squamous cell carcinoma (HNSC), mesothelioma (MESO), stomach adenocarcinoma (STAD), uveal melanoma (UVM) and cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) (p < 0.01). NT5E-related immune microenvironment analysis revealed that NT5E is associated positively with the degree of infiltration of cancer-associated fibroblasts (CAFs) and endothelial cells in most cancers. Enrichment analysis of cellular component (CC) demonstrated the critical part of NT5E played in cell-substrate junction, cell-substrate adherens junction, focal adhesion and external side of plasma membrane. Finally, single-cell analysis of NT5E illuminated that EMT function of CAFs was elevated in basal cell carcinoma (BCC), skin cutaneous melanoma (SKCM), HNSC and PAAD. Conclusion: NT5E could serve as a potential prognostic biomarker for cancers. The potential mechanism may be related to the upregulated EMT function of CAFs, which provides novel inspiration for immunotherapy by targeting CAFs with high NT5E expression.

15.
Front Microbiol ; 11: 562775, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33072024

RESUMO

Drought limits crop productivity, especially of sugarcane, which is predominantly grown in the subtropical parts of China. Soil microbes perform a wide range of functions that are important for plant productivity and responses to drought stress, and fungi play an important role in plant-soil interactions. The Ea-DREB2B gene of sugarcane, Saccharum arundinaceum, is involved in regulating the response to drought stress. In this study, fungal communities of the transgenic (TG) sugarcane variety GN18, harboring the drought-tolerant gene Ea-DREB2B and its corresponding non-TG wild-type (WT) variety, FN95-1702, were investigated in three soil compartments (rhizoplane, rhizosphere, and bulk soil) by assessing the internal transcribed spacer region using Illumina MiSeq. As the soil microbial community is also affected by various environmental factors, such as pH, carbon availability, and soil moisture, we determined the total carbon (TC), total nitrogen (TN), and total phosphorus (TP) contents in the rhizoplane, rhizosphere, and bulk soil compartments to explore the associations between soil fungal communities and host plant characteristics. The differences between the soil fungal communities of TG and WT plants were detected. The alpha diversity of TG fungal communities was more correlated to environmental factors than the beta diversity. The abundance of operational taxonomic units (OTUs) enriched in TG root-related area was far more than that in the root-related area of WT plants. Thereinto, more saprotrophs were enriched in the TG root-related area, indicating altered niches of fungal guilds around TG roots. These results revealed that host plant genotype did play a key role for strengthening plant-fungi interaction and enhancing beneficial fungal function in the root-related area (rhizoplane and rhizosphere) of TG sugarcane in order to respond to drought stress.

16.
Front Microbiol ; 11: 704, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32431674

RESUMO

Drought is a major abiotic stress affecting plant growth and development. Sugarcane, a sugar crop planted in warmer climate, suffers dramatically from drought stress. Bacterial communities colonizing the rhizosphere, where roots sense drought stress initially, have been well studied for their beneficial effects on plant growth and health. The Ea-DREB2B gene cloned from the sugarcane, Saccharum arundinaceum, belongs to the DREB2 subgroup of the DREB gene family, which is involved in drought response regulation. Here, we present a detailed characterization of the rhizoplane, rhizosphere, and bulk soil bacterial communities determined using a high-sequencing approach with the transgenic (TG) sugarcane variety GN18 harboring the drought-tolerant Ea-DREB2B gene and its isogenic wild-type (WT) variety FN95-1702 under the same environmental conditions. In addition, the total carbon (TC), total nitrogen (TN), and total phosphorus (TP) contents in each soil area were compared to explore the relationship between bacterial alteration in the TG and WT plants and environmental factors (TC, TN, TP, C:N, C:P, and N:P). Our results showed that the bacterial communities in the rhizosphere and rhizoplane of TG sugarcane were more similar and perfectly correlated with the environmental factors than those of the WT. This suggested that the bacterial communities of the TG plants were altered in response to the changes in root exudates. The results of our study suggest that the change in soil environment caused by transgenic sugarcane alters soil bacterial communities.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31815007

RESUMO

Deregulated telomere length is a causative factor in many physiological and pathological processes, including aging and cancer. Many studies focusing on telomeres have revealed important roles for cooperation between the Shelterin protein complex and telomerase in maintaining telomere length. However, it remains largely unknown whether and how aging-related stresses, such as deregulated protein homeostasis, impact telomere length. Here, we explored the possible roles of aminoacyl tRNA synthetases (AARSs), key enzymes catalyzing the first reactions in protein synthesis, in regulating telomere length and aging. We selected seryl tRNA synthetase (SerRS) since our previous studies discovered expanded functions of SerRS in the nucleus in addition to its canonical cytoplasmic role in protein synthesis. In this study, we revealed that overexpression of SerRS promoted cellular senescence and inhibited the growth of cervical tumor xenografts in mice by triggering the senescence of tumor cells. In the nucleus, SerRS directly bound to telomeric DNA repeats and tethered more POT1 proteins to telomeres through a direct interaction between the UNE-S domain of SerRS and the OB1 domain of POT1. We further demonstrated that SerRS-induced enrichment of POT1 prevented the recruitment of telomerase to telomeres, resulting in progressive telomere shortening. Our data suggested a possible molecular link between protein synthesis and telomere length control, the deregulation of which may be associated with aging and cancer.

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