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Root plays an important role in plant drought tolerance, especially in horticultural crops like apples. However, the crucial regulator and molecular mechanism in root development of apple trees under drought are not well unknown. Cys2/His2-type Zinc-finger proteins are essential for plant response to drought, while the members of C2H2 Zinc-finger proteins in apple are largely unknown. In this study, we identified the members of the C1-2i subclass family of C2H2 Zinc-finger proteins in apple (Malus × domestica). Among them, MdZAT5 is significantly induced in apple roots under drought conditions and positively regulates apple root development under drought. Further investigation revealed that MdZAT5 positively regulates root development and root hydraulic conductivity by mediating the transcription level of MdMYB88 under drought stress. Taken together, our results demonstrate the importance of MdZAT5 in root development under drought in apple trees. This finding provides a new candidate direction for apple breeding for drought resistance.
Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Malus , Proteínas de Plantas , Raízes de Plantas , Malus/genética , Malus/crescimento & desenvolvimento , Malus/metabolismo , Malus/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genéticaRESUMO
BACKGROUND: CDC6 is an oncogenic protein whose expression level fluctuates during the cell cycle. Although several E3 ubiquitin ligases responsible for the ubiquitin-mediated proteolysis of CDC6 have been identified, the deubiquitination pathway for CDC6 has not been investigated. METHODS: The proteome-wide deubiquitinase (DUB) screening was used to identify the potential regulator of CDC6. Immunofluorescence, protein half-life and deubiquitination assays were performed to determine the protein stability of CDC6. Gain- and loss-of-function experiments were implemented to analyse the impacts of OUTD6A-CDC6 axis on tumour growth and chemosensitivity in vitro. N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN)-induced conditional Otud6a knockout (CKO) mouse model and tumour xenograft model were performed to analyse the role of OTUD6A-CDC6 axis in vivo. Tissue specimens were used to determine the association between OTUD6A and CDC6. RESULTS: OTUD6A interacts with, depolyubiquitinates and stabilizes CDC6 by removing K6-, K33-, and K48-linked polyubiquitination. Moreover, OTUD6A promotes cell proliferation and decreases sensitivity to chemotherapy by upregulating CDC6. CKO mice are less prone to BCa tumorigenesis induced by BBN, and knockdown of OTUD6A inhibits tumour progression in vivo. Furthermore, OTUD6A protein level has a positive correlation with CDC6 protein level, and high protein levels of OTUD6A and CDC6 are associated with poor prognosis in patients with bladder cancer. CONCLUSIONS: We reveal an important yet missing piece of novel DUB governing CDC6 stability. In addition, our findings propose a model for the OTUD6A-CDC6 axis that provides novel insights into cell cycle and chemosensitivity regulation, which may become a potential biomarker and promising drug target for cancer treatment.
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Proteínas de Ciclo Celular , Resistencia a Medicamentos Antineoplásicos , Proteínas Nucleares , Ubiquitinação , Animais , Humanos , Camundongos , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Camundongos Knockout , Ensaios Antitumorais Modelo de Xenoenxerto , Regulação Neoplásica da Expressão Gênica , Enzimas Desubiquitinantes/metabolismo , Enzimas Desubiquitinantes/genética , Modelos Animais de DoençasRESUMO
Circular RNAs play important roles in many cancers, including esophageal squamous cell carcinoma (ESCC), but the precise functions of most circular RNAs are poorly understood. Here we detected significant downregulation of circTRPS1-2 in ESCC based on high-throughput sequencing of three pairs of ESCC tissue and adjacent normal tissue, followed by PCR validation with another 30 tissue pairs. Patients with ESCC whose circTRPS1-2 expression was below the median level for the sample showed significantly shorter median overall survival (13 months) than patients whose circTRPS1-2 expression was above the median (36 months). Overexpressing circTRPS1-2 in the human ESCC cell lines K150 and E109, which express low endogenous levels of circTRPS1-2, inhibited cell proliferation and migration. Conversely, knocking down circTRPS1-2 using short interfering RNA promoted cell proliferation and migration. Similar results were observed in mice bearing K150 xenografts in which circTRPS1-2 was overexpressed or knocked down. Several ribosomal proteins co-immunoprecipitated with circTRPS1-2 from K150 cells in culture, and K150 cells overexpressing circTRPS1-2 showed reduced numbers of ribosomes by A260 absorbance measure and electron microscopy. Our results suggest that circTRPS1-2 can inhibit ESCC proliferation and migration by reducing the production of ribosomes, establishing its potential usefulness in ESCC treatment and prediction of prognosis.
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PURPOSE: Radiation-induced myocardial fibrosis (RIMF) is a severe delayed complication of thoracic irradiation (IR). Endothelin-1 (ET-1) is critical in cardiac fibroblast activation, and docosahexaenoic acid (DHA) is protective against various cardiac diseases. This study aimed to explore the roles of ET-1 in RIMF and the potential of DHA in preventing RIMF. METHODS AND MATERIALS: Hematoxylin and eosin, sirius red, and Masson trichrome staining were carried out to evaluate the histopathologic conditions in mouse models. Enzyme-linked immunosorbent assays were used to detect the concentration of ET-1 in serum and cell supernatants. Western blotting, immunofluorescence, and immunohistochemistry were used to assess the protein levels. The phenotypic alterations of cardiac fibroblasts were evaluated by cell proliferation/migration assays and α-smooth muscle actin (α-SMA) detection. RESULTS: Radiation increased ET-1 expression and secretion by increasing p38 phosphorylation in cardiomyocytes, and ET-1 markedly promoted the activation of cardiac fibroblasts, which were characterized by enhanced fibroblast proliferation, migration, and α-SMA expression. Cardiomyocyte-derived ET-1 mediated radiation-induced fibroblast activation by targeting the PI3K-AKT and MEK-ERK pathways in fibroblasts. DHA suppressed ET-1 levels by blocking p38 signaling in cardiomyocytes and significantly attenuated the activation of cardiac fibroblasts induced by the IR/ET-1 axis. Importantly, DHA decreased collagen deposition and α-SMA expression, alleviating cardiac fibrosis caused by radiation in mouse models. CONCLUSIONS: Our findings demonstrate that radiation facilitates cardiac fibroblast activation by enhancing p38/ET-1 signaling in cardiomyocytes, revealing the IR/p38/ET-1 regulatory axis in RIMF for the first time. DHA effectively inhibits fibroblast activation by targeting p38/ET-1 and can be recognized as a promising protective agent against RIMF.
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Endotelina-1 , Miócitos Cardíacos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Endotelina-1/metabolismo , Endotelina-1/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Docosa-Hexaenoicos/uso terapêutico , Ácidos Docosa-Hexaenoicos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fibrose , Fibroblastos/metabolismoRESUMO
PURPOSE: Radiation-induced lung fibrosis (RILF) is a serious late complication of thoracic radiation therapy. Inflammation is crucial in fibroblast activation and RILF, and arachidonic acid (AA) is an important inflammatory mediator released by cytosolic phospholipase A2 (cPLA2) and reduced by arachidonyl trifluoromethyl ketone (ATK)-targeting of cPLA2. Here, we aimed to investigate the roles of the cPLA2/AA pathway in RILF and assess the potential of targeting cPLA2 to prevent RILF. METHODS AND MATERIALS: A computed tomography scan was used to obtain the mean lung density, and hematoxylin-eosin, Masson's trichrome, and Sirius Red staining were used to assess the histopathologic conditions in mouse models. AA levels in mouse serum and cell supernatants were tested by enzyme-linked immunosorbent assay. Fibroblast phenotype alterations were examined by a Cell Counting Kit-8, manual cell counting, and a Transwell system. The protein levels were evaluated via Western blotting, immunofluorescence, and immunohistochemistry. RESULTS: AA protected fibroblasts against radiation-induced growth inhibition and promoted fibroblast activation, which was characterized by enhanced α-smooth muscle actin expression and migration capacity. Radiation could activate fibroblasts by upregulating cPLA2 expression and AA production, which could be reversed by ATK. Moreover, inhibiting cPLA2 with ATK significantly attenuated collagen deposition and radiation-induced pulmonary fibrosis in mouse models. We further identified extracellular-signal regulated protein kinase (ERK) as the downstream target of the radiation-AA regulatory axis. Radiation-induced AA increased phosphorylated-ERK levels, promoting cyclinD1, cyclin-dependent kinase 6, and α-smooth muscle actin expression and contributing to fibroblast activation. Inhibiting P-ERK impaired radiation- and AA-induced fibroblast activation. The related molecular mechanisms were verified using specimens from animal models. CONCLUSIONS: Our findings uncover the role of the cPLA2/AA-ERK regulatory axis in response to radiation in pulmonary fibroblast activation and recognize cPLA2 as the key regulatory molecule during RILF for the first time. Targeting cPLA2 may be a promising protective strategy against RILF.
Assuntos
Fibrose Pulmonar , Camundongos , Animais , Ácido Araquidônico/farmacologia , Ácido Araquidônico/metabolismo , Fosfolipases A2 , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/prevenção & controle , Actinas , Citosol/metabolismo , Pulmão/metabolismoRESUMO
Background: As a potent inhibitor of the vascular endothelial growth factor (VEGF) signaling pathway, Apatinib has been used in antitumor treatment for some time. The study aimed to research the therapeutic effects and toxicity of Apatinib in the treatment of advanced non-small cell lung cancer (NSCLC). Methods: We retrospectively analyzed 128 NSCLC patients treated with Apatinib in Qilu Hospital of Shandong University. Response Evaluation Criteria in Solid Tumors (RECIST) criteria was adopted to evaluate the treatment effect, and Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 was conducted to determine the Adverse Events (AEs). Cox proportional hazard model and Kaplan-Meier function were applied to evaluate the progression-free survival (PFS) and overall survival (OS). Results: Among 128 NSCLC patients, partial response (PR) were observed in 15 patients, stable disease (SD) in 66 patients and progressive disease (PD) in 47 patients. The objective response rate (ORR) and disease control rate (DCR) accounted for 11.7% and 63.3% respectively. The median PFS (mPFS) and median OS (mOS) were 4.4 months and 17.2 months. Common side effects of Apatinib were hypertension (n=48), proteinuria (n=35), and hand-foot syndrome (HFS) (n=30), all of the side effects were controllable. No significant difference was observed in efficacy and AEs between the higher dose group (Apatinib>500mg/d) and the lower dose group (Apatinib=500mg/d). Conclusions: The study suggested that Apatinib with a lower dose (=500mg/d) has good efficacy and safety in the treatment of advanced NSCLC after first-line chemotherapy.
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Radiotherapy is one of the most effective treatments for esophageal squamous cell carcinoma (ESCC); however, radioresistance is a clinical problem that must urgently be solved. Here, we found that butyrophilin subfamily 3 member A1 (BTN3A1) is upregulated in ESCC tumor tissues compared with nontumor tissues. We also evaluated BTN3A1 expression in patients with ESCC receiving adjuvant radiotherapy. The results demonstrated that BTN3A1 upregulation predicts a poor prognosis for ESCC patients. BTN3A1 overexpression promotes ESCC cell proliferation in vitro and in vivo. Moreover, BTN3A1 knockdown sensitized ESCC cells to radiation. We further explored the mode of death involved in BTN3A1-mediated radioresistance. Previous studies have shown that apoptosis, autophagy, necrosis, pyroptosis and ferroptosis are important for the survival of ESCC cells. We performed an RT-PCR array and western blotting (WB) to identify the mode of death and revealed for the first time that BTN3A1 promotes cell radioresistance by activating autophagy. In addition, by performing immunoprecipitation and mass spectrometry analyses, we found that BTN3A1 regulated the expression of UNC-51-like autophagy activating kinase 1(ULK1) and promoted its phosphorylation to subsequently initiate autophagy. Chromatin immunoprecipitation (ChIP) and luciferase reporter assay results indicated that BTN3A1 is a novel direct target of hypoxia inducible factor-1α (HIF-1α). HIF-1α, a transcription factor, promotes BTN3A1 transcription upon irradiation. Overall, the present study is the first to show that BTN3A1 plays a key role in radioresistance and that targeting BTN3A1 might be a promising strategy to improve radiotherapy efficacy in patients with ESCC.
Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/radioterapia , Carcinoma de Células Escamosas do Esôfago/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/metabolismo , Linhagem Celular Tumoral , Autofagia/genética , Apoptose/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Butirofilinas , Antígenos CDRESUMO
Pyroptosis is a programmed cell death characterized by inflammation and may coordinate with cancer immunotherapy, but assessments of pyroptosis in patients with immunotherapy are lacking. We evaluated the pyroptosis potentials in 71 cohorts with 24,388 cancer patients. They were elevated in tumors compared to normal tissues but had a weak relationship with prognosis. High pyroptosis potentials indicated "hot tumors" characteristics and high objective response rates to PD1/PDL1 inhibitors derived from clinical trials. In 15 cohorts with patients treated with immunotherapy, a pyroptosis score showed predictive values in objective response rate, progression-free survival, and overall survival. Systematic treatments, such as chemotherapy or endocrine therapy, enhanced pyroptosis in drug-resistant tumors. These results were further validated in three independent clinical cohorts and our two institutional cohorts by immunohistochemistry. Our findings uncover a value of pyroptosis potentials to predict immunotherapy responses and a theoretical rationale for combining pyroptosis inducers and immunotherapy in cancer treatment.
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Neoplasias , Piroptose , Humanos , Imunoterapia , Neoplasias/tratamento farmacológico , Microambiente TumoralRESUMO
Drought limits apple yield and fruit quality. However, the molecular mechanism of apple in response to drought is not well known. Here, we report a Cys2/His2 (C2H2)-type zinc-finger protein, MdZAT5, that positively regulates apple drought tolerance by regulating drought-responsive RNAs and microRNAs (miRNAs). DNA affinity purification and sequencing and yeast-one hybrid analysis identified the binding motifs of MdZAT5, T/ACACT/AC/A/G. Chromatin immunoprecipitation quantitative polymerase chain reaction (ChIP-qPCR) and electrophoretic mobility shift assays (EMSAs) showed that MdZAT5 directly binds to the promoters of the drought-responsive genes including MdRHA2a, MdLEA14, MdTPX1, and MdCAT3, and activates their expression under drought stress. MdZAT5 interacts with and directly targets HYPONASTIC LEAVES1 (MdHYL1). MdZAT5 may facilitate the interaction of MdHYL1 with pri-miRNAs or MdDCL1 by activating MdHYL1 expression, thereby regulating the biogenesis of drought-responsive miRNAs. Genetic dissection showed that MdHYL1 is essential for MdZAT5-mediated drought tolerance and miRNA biogenesis. In addition, ChIP-qPCR and EMSA revealed that MdZAT5 binds directly to the promoters of some MIR genes including Mdm-miR171i and Mdm-miR172c, and modulates their transcription. Taken together, our findings improve our understanding of the molecular mechanisms of drought response in apple and provide a candidate gene for the breeding of drought-tolerant cultivars.
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Malus , MicroRNAs , Secas , Malus/genética , MicroRNAs/genética , Regulação da Expressão Gênica de Plantas , RNA Mensageiro , Melhoramento Vegetal , Estresse Fisiológico/genéticaRESUMO
The expression of CD155 has been observed to increase in various human cancers, but its role in the development of esophageal cancer (EC) is unclear. Radiotherapy is one of the primary therapeutic options for EC. However, radioresistance is still a severe issue in EC treatment. In this study, Oncomine database mining, immunohistochemistry, and survival analysis showed that higher expression of CD155 in patients with EC than in healthy controls. In vitro and in vivo, we found for the first time that irradiation increased the expression of CD155 in EC cells. CD155 knockdown inhibited cell proliferation and migration and tumor formation, and significantly increased radiosensitivity in EC. The in vivo model with high CD155 expression significantly promoted the proliferation and migration of EC cells. Furthermore, increased CD155 expression was associated with poor prognosis in patients with EC. CD155 regulated the Hippo-Yap pathway, influencing cell proliferation and migration. Therefore, CD155 is essential for the proliferation, migration, and radioresistance of EC. CD155 inhibition may be a viable strategy for improving radiation treatment efficacy in individuals with EC.
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Animals constantly receive various sensory stimuli, such as odours, sounds, light and touch, from the surrounding environment. These sensory inputs are essential for animals to search for food and avoid predators, but they also affect their physiological status, and may cause diseases such as cancer. Malignant gliomas-the most lethal form of brain tumour1-are known to intimately communicate with neurons at the cellular level2,3. However, it remains unclear whether external sensory stimuli can directly affect the development of malignant glioma under normal living conditions. Here we show that olfaction can directly regulate gliomagenesis. In an autochthonous mouse model that recapitulates adult gliomagenesis4-6 originating in oligodendrocyte precursor cells (OPCs), gliomas preferentially emerge in the olfactory bulb-the first relay of brain olfactory circuitry. Manipulating the activity of olfactory receptor neurons (ORNs) affects the development of glioma. Mechanistically, olfaction excites mitral and tufted (M/T) cells, which receive sensory information from ORNs and release insulin-like growth factor 1 (IGF1) in an activity-dependent manner. Specific knockout of Igf1 in M/T cells suppresses gliomagenesis. In addition, knocking out the IGF1 receptor in pre-cancerous mutant OPCs abolishes the ORN-activity-dependent mitogenic effects. Our findings establish a link between sensory experience and gliomagenesis through their corresponding sensory neuronal circuits.
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Carcinogênese , Glioma , Fator de Crescimento Insulin-Like I , Neurônios Receptores Olfatórios , Olfato , Animais , Glioma/metabolismo , Glioma/patologia , Camundongos , Vias Neurais , Bulbo Olfatório/patologia , Neurônios Receptores Olfatórios/fisiologia , Olfato/fisiologiaAssuntos
Genoma de Planta , Malus , Cromossomos , Malus/genética , Folhas de Planta , Estresse Fisiológico/genéticaRESUMO
BACKGROUND: Second-generation programmed cell death-protein 1/programmed death-ligand 1 (PD-1/PD-L1) inhibitors, such as bintrafusp alfa (M7824), SHR-1701, and YM101, have been developed to simultaneously block PD-1/PD-L1 and transforming growth factor-beta/transforming growth factor-beta receptor (TGF-ß/TGF-ßR). Consequently, it is necessary to identify predictive factors of lung cancer patients who are not only resistant to PD-1/PD-L1 inhibitors but also sensitive to bifunctional drugs. The purpose of this study was to search for such predictors. METHODS: Multivariable Cox regression was used to study the association between the clinical outcome of treatment with PD-1/PD-L1 inhibitors and lymphocyte recovery after lymphopenia in lung cancer patients. Murine CMT167 lung cancer cells were engineered to express the firefly luciferase gene and implanted orthotopically in the lung of syngeneic mice. Bioluminescence imaging, flow cytometry, and immunohistochemistry were employed to determine response to immunotherapy and function of tumor-infiltrating immune cells. RESULTS: For lung cancer patients treated with anti-PD-1/PD-L1 antibodies, poor lymphocyte recovery was associated with a shorter progression-free survival (PFS; P < 0.001), an accumulation of regulatory T cells (Tregs), and an elimination of CD8+ T cells in the peripheral blood. Levels of CD8+ T cells and Treg cells were also imbalanced in the tumors and peripheral immune organs of mice with poor lymphocyte recovery after chemotherapy. Moreover, these mice failed to respond to anti-PD-1 antibodies but remained sensitive to the anti-PD-L1/TGF-ßR fusion protein (SHR-1701). Consistently, SHR-1701 but not anti-PD-1 antibodies, markedly enhanced IFN-γ production and Ki-67 expression in peripheral CD8+ T cells from patients with impaired lymphocyte recovery. CONCLUSIONS: Lung cancer patients with poor lymphocyte recovery and suffering from persistent lymphopenia after previous chemotherapy are resistant to anti-PD-1/PD-L1 antibodies but might be sensitive to second-generation agents such as SHR-1701.
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Antígeno B7-H1 , Neoplasias Pulmonares , Animais , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Linfócitos T CD8-Positivos , Humanos , Inibidores de Checkpoint Imunológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Camundongos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/genéticaRESUMO
SUMOylation is involved in various aspects of plant biology, including drought stress. However, the relationship between SUMOylation and drought stress tolerance is complex; whether SUMOylation has a crosstalk with ubiquitination in response to drought stress remains largely unclear. In this study, we found that both increased and decreased SUMOylation led to increased survival of apple (Malus × domestica) under drought stress: both transgenic MdSUMO2A overexpressing (OE) plants and MdSUMO2 RNAi plants exhibited enhanced drought tolerance. We further confirmed that MdDREB2A is one of the MdSUMO2 targets. Both transgenic MdDREB2A OE and MdDREB2AK192R OE plants (which lacked the key site of SUMOylation by MdSUMO2A) were more drought tolerant than wild-type plants. However, MdDREB2AK192R OE plants had a much higher survival rate than MdDREB2A OE plants. We further showed SUMOylated MdDREB2A was conjugated with ubiquitin by MdRNF4 under drought stress, thereby triggering its protein degradation. In addition, MdRNF4 RNAi plants were more tolerant to drought stress. These results revealed the molecular mechanisms that underlie the relationship of SUMOylation with drought tolerance and provided evidence for the tight control of MdDREB2A accumulation under drought stress mediated by SUMOylation and ubiquitination.
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Malus , Secas , Regulação da Expressão Gênica de Plantas/genética , Malus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , SumoilaçãoRESUMO
Drought significantly limits apple fruit production and quality. Decoding the key genes involved in drought stress tolerance is important for breeding varieties with improved drought resistance. Here, we identified GRETCHEN HAGEN3.6 (GH3.6), an indole-3-acetic acid (IAA) conjugating enzyme, to be a negative regulator of water-deficit stress tolerance in apple. Overexpressing MdGH3.6 reduced IAA content, adventitious root number, root length and water-deficit stress tolerance, whereas knocking down MdGH3.6 and its close paralogs increased IAA content, adventitious root number, root length and water-deficit stress tolerance. Moreover, MdGH3.6 negatively regulated the expression of wax biosynthetic genes under water-deficit stress and thus negatively regulated cuticular wax content. Additionally, MdGH3.6 negatively regulated reactive oxygen species scavengers, including antioxidant enzymes and metabolites involved in the phenylpropanoid and flavonoid pathway in response to water-deficit stress. Further study revealed that the homolog of transcription factor AtMYB94, rather than AtMYB96, could bind to the MdGH3.6 promoter and negatively regulated its expression under water-deficit stress conditions in apple. Overall, our results identify a candidate gene for the improvement of drought resistance in fruit trees.
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Malus , Desidratação , Secas , Regulação da Expressão Gênica de Plantas/genética , Malus/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Água/metabolismoRESUMO
Drought stress tolerance is a complex trait regulated by multiple factors. Here, we demonstrate that the miRNA160-Auxin Response Factor 17 (ARF17)-HYPONASTIC LEAVES 1 module is crucial for apple (Malus domestica) drought tolerance. Using stable transgenic plants, we found that drought tolerance was improved by higher levels of Mdm-miR160 or MdHYL1 and by decreased levels of MdARF17, whereas reductions in MdHYL1 or increases in MdARF17 led to greater drought sensitivity. Further study revealed that modulation of drought tolerance was achieved through regulation of drought-responsive miRNA levels by MdARF17 and MdHYL1; MdARF17 interacted with MdHYL1 and bound to the promoter of MdHYL1. Genetic analysis further suggested that MdHYL1 is a direct downstream target of MdARF17. Importantly, MdARF17 and MdHYL1 regulated the abundance of Mdm-miR160. In addition, the Mdm-miR160-MdARF17-MdHYL1 module regulated adventitious root development. We also found that Mdm-miR160 can move from the scion to the rootstock in apple and tomato (Solanum lycopersicum), thereby improving root development and drought tolerance of the rootstock. Our study revealed the mechanisms by which the positive feedback loop of Mdm-miR160-MdARF17-MdHYL1 influences apple drought tolerance.
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Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Secas , Ácidos Indolacéticos/metabolismo , Malus/genética , Malus/metabolismo , MicroRNAs/efeitos dos fármacos , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Desidratação/genética , Desidratação/fisiopatologia , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Plantas Geneticamente ModificadasRESUMO
Water deficit is one of the main challenges for apple (Malus × domestica) growth and productivity. Breeding drought-tolerant cultivars depends on a thorough understanding of the drought responses of apple trees. Here, we identified the zinc-finger protein B-BOX 7/CONSTANS-LIKE 9 (MdBBX7/MdCOL9), which plays a positive role in apple drought tolerance. The overexpression of MdBBX7 enhanced drought tolerance, whereas knocking down MdBBX7 expression reduced it. Chromatin immunoprecipitation-sequencing (ChIP-seq) analysis identified one cis-element of MdBBX7, CCTTG, as well as its known binding motif, the T/G box. ChIP-seq and RNA-seq identified 1,197 direct targets of MdBBX7, including ETHYLENE RESPONSE FACTOR (ERF1), EARLY RESPONSIVE TO DEHYDRATION 15 (ERD15), and GOLDEN2-LIKE 1 (GLK1) and these were further verified by ChIP-qPCR and electronic mobility shift assays. Yeast two-hybrid screen identified an interacting protein of MdBBX7, RING-type E3 ligase MYB30-INTERACTING E3 LIGASE 1 (MIEL1). Further examination revealed that MdMIEL1 could mediate the ubiquitination and degradation of MdBBX7 by the 26S proteasome pathway. Genetic interaction analysis suggested that MdMIEL1 acts as an upstream factor of MdBBX7. In addition, MdMIEL1 was a negative regulator of the apple drought stress response. Taken together, our results illustrate the molecular mechanisms by which the MdMIEL1-MdBBX7 module influences the response of apple to drought stress.
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Desidratação/genética , Desidratação/fisiopatologia , Malus/genética , Malus/fisiologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Dedos de Zinco , Produtos Agrícolas/genética , Produtos Agrícolas/fisiologia , Secas , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente ModificadasRESUMO
A terthiophene-functionalized mesoporous SBA-15 silica, i.e., TTU-SBA-15, was successfully developed and used as a highly selective and ultrasensitive fluorescence sensor for methyl orange (MO) detection. When the concentration of MO was increased, the fluorescence emission intensity of TTU-SBA-15 suspensions at 452 nm gradually decreased at an excitation wavelength of 368 nm, and the color of the suspension solutions changed obviously from blue to dark under 365 nm UV light. The fluorescence intensity at 452 nm was linearly proportional to the concentration of MO in the range 0.20 - 2.0 µM, with a detection limit of 0.092 µM. Competitive pollutants, variations in pH, and sample recycling had subtle or negligible effects on the detection of MO. TTU-SBA-15 was applied to the determination of MO in tap water, and recoveries from spiked samples were in the range 98.3 - 103.0%. This study provides a convenient and effective strategy to realize highly sensitive and selective sensors that could target dyes via the functional modification of mesoporous materials.
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Compostos Azo/química , Fluorescência , Dióxido de Silício/química , Tiofenos/química , Estrutura Molecular , Porosidade , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
N6-Methyladenosine (m6A) is the most prevalent epigenetic RNA modification and is vital in regulating malignancies. The roles of m6A modifiers on noncoding RNAs have not been fully investigated in esophageal cancer. By screening all m6A modifiers, ALKBH5 was the most potent member related to patient outcomes and suppressing esophageal cancer malignancy in cell and animal models. It demethylated pri-miR-194-2 and inhibited miR-194-2 biogenesis through an m6A/DGCR8-dependent manner. RAI1, previously considered as a circadian clock transcriptional regulator, was the main target of miR-194-2. It enhanced transcription of Hippo pathway upstream genes by binding to their 3'UTR and suppressed YAP/TAZ nuclear translocation. The ALKBH5/miR-194-2/RAI1 axis was also validated in clinical samples. In addition, the increased malignancy by low ALKBH5 was abolished by the YAP inhibitor verteporfin. Our findings uncover a critical role of ALKBH5 in miRNAs biogenesis and provide novel insight for developing treatment strategies in esophageal cancer.
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Neoplasias Esofágicas , Adenosina/análogos & derivados , Comunicação Celular , Via de Sinalização Hippo , Humanos , MicroRNAs , Proteínas de Ligação a RNARESUMO
The evolutionary history of the Malus genus has not been well studied. In the current study, we presented genetic evidence on the origin of the Malus genus based on genome sequencing of 297 Malus accessions, revealing the genetic relationship between wild species and cultivated apples. Our results demonstrated that North American and East Asian wild species are closer to the outgroup (pear) than Central Asian species, and hybrid species including natural (separated before the Pleistocene, about 2.5 Mya) and artificial hybrids (including ornamental trees and rootstocks) are between East and Central Asian wild species. Introgressions from M. sylvestris in cultivated apples appeared to be more extensive than those from M. sieversii, whose genetic background flowed westward across Eurasia and eastward to wild species including M. prunifolia, M. × asiatica, M. × micromalus, and M. × robust. Our results suggested that the loss of ancestral gene flow from M. sieversii in cultivated apples accompanied the movement of European traders around the world since the Age of Discovery. Natural SNP variations showed that cultivated apples had higher nucleotide diversity than wild species and more unique SNPs than other apple groups. An apple ERECTA-like gene that underwent selection during domestication on 15th chromosome was identified as a likely major determinant of fruit length and diameter, and an NB-ARC domain-containing gene was found to strongly affect anthocyanin accumulation using a genome-wide association approach. Our results provide new insights into the origin and domestication of apples and will be useful in new breeding programmes and efforts to increase fruit crop productivity.