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PURPOSE: The detection rate of Salmonella enterica serovar 1,4,[5], 12: i: - (S. 1,4,[5], 12: i: -) has increased as the most common serotype globally. A S. 1,4,[5], 12: i: - strain named ST3606 (sequence type 34), isolated from a fecal specimen of a child with acute diarrhea hospitalized in a tertiary hospital in China, was firstly reported to be resistant to carbapenem and ceftazidime-avibactam. The aim of this study was to characterize the whole-genome sequence of S. 1,4,[5], 12: i: - isolate, ST3606, and explore its antibiotic resistance genes and their genetic environments. METHODS: The genomic DNA of S. 1,4,[5], 12: i: - ST3606 was extracted and performed with single-molecule real-time sequencing. Resistance genes, plasmid replicon type, mobile elements, and multilocus sequence types (STs) of ST3606 were identified by ResFinder 3.2, PlasmidFinder, OriTfinder database, ISfinder database, and MLST 2.0, respectively. The conjugation experiment was utilized to evaluate the conjugation frequency of pST3606-2. Protein expression and enzyme kinetics experiments of CTX-M were performed to analyze hydrolytic activity of a novel CTX-M-261 enzyme toward several antibiotics. RESULTS: Single-molecule real-time sequencing revealed the coexistence of a 109-kb IncI1-Iα plasmid pST3606-1 and a 70.5-kb IncFII plasmid pST3606-2. The isolate carried resistance genes, including blaNDM-5, sul1, qacE, aadA2, and dfrA12 in pST3606-1, blaTEM-1B, aac(3)-lld, and blaCTX-M-261, a novel blaCTX-M-1 family member, in pST3606-2, and aac(6')-Iaa in chromosome. The blaCTX-M-261 was derived from blaCTX-M-55 by a single-nucleotide mutation 751G>A leading to amino acid substitution of Val for Met at position 251 (Val251Met), which conferred CTX-M increasing resistance to ceftazidime verified by antibiotics susceptibility testing of transconjugants carrying pST3606-2 and steady-state kinetic parameters of CTX-M-261. pST3606-1 is an IncI1-α incompatibility type that shares homology with plasmids of pC-F-164_A-OXA140, pE-T654-NDM-5, p_dm760b_NDM-5, and p_dmcr749c_NDM-5. The conjugation experiment demonstrated that pST3606-2 was successfully transferred to the Escherichia coli recipient C600 with four modules of OriTfinder. CONCLUSION: Plasmid-mediated horizontal transfer plays an important role in blaNDM-5 and blaCTX-M-261 dissemination, which increases the threat to public health due to the resistance to most ß-lactam antibiotics. This is the first report of blaCTX-M-261 and blaNDM-5 in S. 1,4,[5], 12: i: -. The work provides insights into the enzymatic function and demonstrates the ongoing evolution of CTX-M enzymes and confirms urgency to control resistance of S. 1,4,[5], 12: i: -.
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Antibacterianos , Compostos Azabicíclicos , Ceftazidima , Combinação de Medicamentos , Testes de Sensibilidade Microbiana , Infecções por Salmonella , Salmonella enterica , beta-Lactamases , Ceftazidima/farmacologia , Humanos , China , beta-Lactamases/genética , beta-Lactamases/metabolismo , Compostos Azabicíclicos/farmacologia , Antibacterianos/farmacologia , Salmonella enterica/genética , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/enzimologia , Infecções por Salmonella/microbiologia , Sequenciamento Completo do Genoma , Farmacorresistência Bacteriana Múltipla/genética , Sorogrupo , Plasmídeos/genética , Fezes/microbiologia , Genoma BacterianoRESUMO
Anthurium andraeanum Linden is a prominent ornamental plant belonging to the family Araceae and is cultivated worldwide. The morphology characteristics are crucial because they significantly impact ornamental values, commercial properties, and the efficiency of space utilization in production. However, only a few related investigations have been conducted in anthurium to date. In this study, an F1 genetic segregation population containing 160 progenies was generated through hybridization between potted and cut anthurium varieties. Fifteen morphological traits were assessed and revealed substantial levels of genetic variation and widespread positive correlation. Based on specific length amplified fragment (SLAF) sequencing technology, 8171 single nucleotide polymorphism (SNP) markers were developed, and the high-density linkage map of 2202.27 cM in length distributed on 15 linkage groups was constructed successfully, with an average distance of 0.30 cM. Using the inclusive composite interval mapping (ICIM) method, 59 QTLs related to 15 key morphological traits were successfully identified, which explained phenotypic variance (PVE) ranging from 6.21% to 17.74%. Thirty-three of those associated with 13 traits were designated as major QTLs with PVE > 10%. These findings offer valuable insights into the genetic basis of quantitative traits and are beneficial for molecular marker-assisted selection (MAS) in anthurium breeding.
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OBJECTIVE: The present study aimed to investigate the association of triglyceride-glucose (TyG) index and neutrophil-to-lymphocyte ratio (NLR) with coronary artery disease (CAD), and evaluate the cumulative value of TyG index and NLR in identifying CAD, as well as the severity of CAD. METHODS: This retrospective study enrolled 2867 patients who underwent coronary angiography (CAG) for the first time between January 2013 and June 2022 in Zhongnan Hospital of Wuhan University. There were 2109 patients with CAD and 758 patients without CAD. The CAD patients were divided into two groups based on the median of Gensini score (mild stenosis CAD group: Gensini score < 26 points; severe stenosis CAD group: Gensini score ≥ 26 points). To further evaluate the cumulative value of TyG index and NLR in identifying CAD and CAD severity, all patients were classified into four groups based on median of TyG index and NLR: (1) the control group: patients with low-TyG and low-NLR; (2) isolated high-NLR group: patients with low-TyG and high- NLR; (3) isolated high- TyG group: patients with high-TyG and low- NLR; (4) high-TyG combined with high-NLR group: patients with high-TyG and high- NLR. RESULTS: Multivariate logistic regression analysis showed that both the TyG index and NLR were independent risk factors for CAD, and they were also independent risk factors for severe stenosis in CAD (P < 0.05). Compared with the low-TyG and low- NLR group, patients in high-TyG and high- NLR group had a 1.418 times higher odds ratio (OR) of having CAD and a 1.692 times higher OR of having severe stenosis in CAD in the multivariable logistic regression model. It is worth noting that the OR values of the high-TyG and high- NLR group were higher than those of the isolated high-NLR group and the isolated high- TyG group. The ROC analysis showed that the combination of the TyG index and NLR was superior to TyG index or NLR in predicting CAD and CAD severity. CONCLUSION: Compared to TyG index or NLR, the combination of the TyG index and NLR is beneficial to improve the diagnostic accuracy of CAD and CAD severity.
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Doença da Artéria Coronariana , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Glucose , Neutrófilos , Estudos Retrospectivos , Constrição Patológica , Triglicerídeos , Linfócitos , Fatores de Risco , Biomarcadores , GlicemiaRESUMO
To fire action-potential-like electrical signals, the vacuole membrane requires the two-pore channel TPC1, formerly called SV channel. The TPC1/SV channel functions as a depolarization-stimulated, non-selective cation channel that is inhibited by luminal Ca2+. In our search for species-dependent functional TPC1 channel variants with different luminal Ca2+ sensitivity, we found in total three acidic residues present in Ca2+ sensor sites 2 and 3 of the Ca2+-sensitive AtTPC1 channel from Arabidopsis thaliana that were neutral in its Vicia faba ortholog and also in those of many other Fabaceae. When expressed in the Arabidopsis AtTPC1-loss-of-function background, wild-type VfTPC1 was hypersensitive to vacuole depolarization and only weakly sensitive to blocking luminal Ca2+. When AtTPC1 was mutated for these VfTPC1-homologous polymorphic residues, two neutral substitutions in Ca2+ sensor site 3 alone were already sufficient for the Arabidopsis At-VfTPC1 channel mutant to gain VfTPC1-like voltage and luminal Ca2+ sensitivity that together rendered vacuoles hyperexcitable. Thus, natural TPC1 channel variants exist in plant families which may fine-tune vacuole excitability and adapt it to environmental settings of the particular ecological niche.
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Arabidopsis , Vicia faba , Vacúolos , Arabidopsis/genética , Potenciais de Ação , EcossistemaRESUMO
Aldo-keto reductase family 1 member B10 (AKR1B10) is a potential marker of several types of cancer; however, the role of AKR1B10 in nasopharyngeal carcinoma (NPC) remains unclear. In the present study, AKR1B10 RNA-seq data and clinical information were obtained from The Cancer Genome Atlas head and neck squamous cell carcinoma (HNSCC) database to evaluate the role of AKR1B10 in HNSCC. There was no statistically significant difference in the expression of AKR1B10 between HNSCC tissues and adjacent normal tissues, and high AKR1B10 expression was not associated with poor overall survival according to the public database. The present study further examined the role of AKR1B10 in patients with NPC using data obtained from the Gene Expression Omnibus database. Analysis of the GSE53819 and GSE61218 datasets showed that the there were no significant differences in the expression levels of AKR1B10 between NPC tissues and normal tissues. However, analysis of the GSE103611 dataset indicated that AKR1B10 may be associated with distance metastasis following radical treatment in NPC. Finally, serum samples from patients with NPC and healthy controls were collected and analyzed. The results revealed that AKR1B10 levels were significantly increased in samples from patients with NPC compared with those from healthy controls, and the area under the receiver operating characteristic curve was 0.909. In conclusion, unlike tissue AKR1B10 expression, serum AKR1B10 levels may be a promising biomarker for the diagnosis of NPC.
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The musty odorant (2-methylisoborneol, MIB) is prevalent in source water reservoirs and has become one of the major challenges for drinking water quality. This study proposes an approach to control the growth of MIB-producing cyanobacteria in a small reservoir based on hydraulic regulation, according to the results of long-term field investigations, laboratory culture experiments, model construction, and field application. Field investigations found that longer hydraulic retention time (HRT) is a factor that triggers MIB episodes. The culture study revealed that the maximum cell density, growth rate of MIB-producing Planktothricoides raciborskii, and MIB concentration are determined by the HRT (R2= 0.94, p-value < 0.001) and can be minimized by decreasing the HRT to less than 10 d. On this basis, an HRT regulation model was constructed and validated by field investigation, and critical HRT values were evaluated for 14 cyanobacteria genera. By decreasing the HRT to 5.4 ± 0.8 d, which is lower than the critical value of 7.5 â¼ 15.0 d, an MIB episode was successfully terminated in ZXD Reservoir in 2021. The results suggest that the proposed principle can provide a scientific basis for HRT regulation, which has been proved to be effective and feasible. This approach avoids negative impacts on water quality, does not require extra investment in engineering infrastructure, and in some cases may be applied readily by changing existing operational procedures. Therefore, HRT-based regulation is a promising strategy targeting MIB control and possibly for other cyanobacterial-derived water quality problems in small reservoirs.
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Água Potável , Odorantes/análise , Qualidade da ÁguaRESUMO
In comparison with the middle- and high-latitude regions, the low-latitude regions are less associated with the occurrence of 2-methylisoborneol (MIB) episodes, since most of the previously identified MIB producers favor moderate/low light/temperature conditions. Here, we report a serious MIB outbreak over the period from Jul. 2018 to Jun. 2019 in a low-latitude reservoir with a mean annual water temperature of 25.6 °C. The MIB episode lasted for a long period, from Jul. 2018 to Jan. 2019, and Planktothricoides raciborskii was confirmed to be the main MIB producer. The growth characteristics of P. raciborskii were explored through both laboratory culturing and on-site verification experiments. The results indicated that this strain was not nutrient-sensitive at TN > 800 µg L-1 and TP > 10 µg L-1, but favored moderate light intensity (54 µmol photon m-2·s-1) and high temperature (30 °C). The two bloom-forming genera, Limnothrix and Aphanizomenon, favoring lower temperature and similar or relatively higher light intensity, showed much greater proliferation, about 13 folds (Limnothrix) and 58 folds (Aphanizomenon), from Dec. to Jun.; by contrast, the high water temperature (29.9 ± 2.8 °C) and light intensity (189.1 ± 87.6 µmol photon m-2·s-1) from Jul. to Nov. were not favorable to Limnothrix or Aphanizomenon, which might have created an opportunity for the growth of MIB-producing P. raciborskii. In addition, we also found that high temperature could promote the release of MIB from P. raciborskii cells, therefore exerting increased pressure on drinking water treatment processes.
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Aphanizomenon , Cianobactérias , Luz , Odorantes , TemperaturaRESUMO
Voltage-gated ion channels confer excitability to biological membranes, initiating and propagating electrical signals across large distances on short timescales. Membrane excitation requires channels that respond to changes in electric field and couple the transmembrane voltage to gating of a central pore. To address the mechanism of this process in a voltage-gated ion channel, we determined structures of the plant two-pore channel 1 at different stages along its activation coordinate. These high-resolution structures of activation intermediates, when compared with the resting-state structure, portray a mechanism in which the voltage-sensing domain undergoes dilation and in-membrane plane rotation about the gating charge-bearing helix, followed by charge translocation across the charge transfer seal. These structures, in concert with patch-clamp electrophysiology, show that residues in the pore mouth sense inhibitory Ca2+ and are allosterically coupled to the voltage sensor. These conformational changes provide insight into the mechanism of voltage-sensor domain activation in which activation occurs vectorially over a series of elementary steps.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Canais Iônicos/metabolismo , Proteínas de Arabidopsis/química , Cálcio/metabolismo , Microscopia Crioeletrônica , Ativação do Canal Iônico , Ligantes , Conformação ProteicaRESUMO
Cyanobacteria release 2-methylisoborneol (MIB) as a secondary metabolite. Here, we propose a reverse transcription quantitative real-time PCR (RT-qPCR) based method to evaluate the MIB-producing potential in source water by detecting the MIB-synthesis gene (mic). A MIBQSF/R primer set was designed based on 35 mic gene sequences obtained from 12 pure-cultured MIB-producing strains and 23 sequences from the NCBI database. This primer set successfully identified all known 43 MIB-producing cyanobacterial strains (12 from this study and 31 from the NCBI database), belonging to different genera, showing a wider coverage than previous primer sets. The efficiency of the method was proved by the amplification efficiency (E = 91.23%), R2 of the standard curve (0.999), the limit of detection (LOD, 5.7 fg µL-1), and the limit of quantification (LOQ, 1.86 × 104 gene copies µL-1). Further, the method was verified by the correlation between the mic gene abundance and MIB concentration 50 field samples from different reservoirs (R2 = 0.614, p < 0.001) and one reservoir (R2 = 0.752, p < 0.001), suggesting its potential as an alternative warning tool to evaluate the risk of MIB problems in source water.
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Cianobactérias , Água Potável , Canfanos/análise , Cianobactérias/genética , Cianobactérias/metabolismo , Água Potável/análise , Odorantes/análise , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Odor problems in source water caused by 2-methylisoborneol (MIB) have been a common issue in China recently, posing a high risk to drinking water safety. The earthy-musty odorant MIB has an extremely low odor threshold (4-16 ng/L) and is hard to remove via conventional processes in drinking water plants (DWP), and therefore could easily provoke complaints from consumers. This compound is produced by a group of filamentous cyanobacteria, mainly belonging to Oscillatoriales. Different from the well-studied surface-blooming Microcystis, filamentous cyanobacteria have specific niche characteristics that allow them to stay at a subsurface or deep layer in the water column. The underwater bloom of these MIB producers is therefore passively determined by the underwater light availability, which is governed by the cell density of surface scum. This suggests that drinking water reservoirs with relatively low nutrient contents are not able to support surface blooms, but are a fairly good fit to the specialized ecological niche of filamentous cyanobacteria; this could explain the widespread odor problems in source water. At present, MIB is mainly treated in DWP using advanced treatment processes and/or activated carbon, but these post-treatment methods have high cost, and not able to deal with water containing high MIB concentrations. Thus, in situ control of MIB producers in source water is an effective complement and is desirable. Lowering the underwater light availability is a possible measure to control MIB producers according to their niche characteristics, which can be obtained by either changing the water level or other measures.
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Cianobactérias , Água Potável , Microcystis , Purificação da Água , Ecossistema , Odorantes/análiseRESUMO
Coronavirus disease 2019 (COVID-19) is a recently emerged disease with formidable infectivity and high mortality. Emerging data suggest that diabetes is one of the most prevalent comorbidities in patients with COVID-19. Although their causal relationship has not yet been investigated, preexisting diabetes can be considered as a risk factor for the adverse outcomes of COVID-19. Proinflammatory state, attenuation of the innate immune response, possibly increased level of ACE2, along with vascular dysfunction, and prothrombotic state in people with diabetes probably contribute to higher susceptibility for SARS-CoV-2 infection and worsened prognosis. On the other hand, activated inflammation, islet damage induced by virus infection, and treatment with glucocorticoids could, in turn, result in impaired glucose regulation in people with diabetes, thus working as an amplification loop to aggravate the disease. Therefore, glycemic management in people with COVID-19, especially in those with severe illness, is of considerable importance. The insights may help to reduce the fatality in the effort against COVID-19.
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[This retracts the article DOI: 10.7150/thno.28228.].
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COVID-19 , Diabetes Mellitus , Hipertensão , Humanos , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Fatores de Risco , SARS-CoV-2RESUMO
BACKGROUND: Coronavirus disease 2019 (COVID-19) began to spread across Wuhan, China, by the end of 2019, and patients were unable to be hospitalized because medical resources were limited. METHODS: A questionnaire survey was conducted among 108 participants with mild COVID-19 who have isolated at home under the guidance of doctors. The results of the questionnaire and outpatient data were integrated to evaluate participants' compliance with various epidemic prevention measures. RESULTS: During isolation, most participants were able to follow epidemic prevention measures under the guidance of doctors. After 14 d from the start of isolation, 45.37% of the participants recovered. Approximately half of the participants were relieved of symptoms, and most of them were transferred to mobile cabin hospitals to continue isolation. Three participants with worsening symptoms were transferred to the designated hospitals. There were no deaths of the participants, but there were 7 family members that were infected. CONCLUSIONS: During a period of home isolation under the guidance of a doctor, individuals can comply with epidemic prevention measures and symptoms can be improved. Scientific home isolation may be an effective way to relieve the strain of medical and social resources during the epidemic of COVID-19.
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COVID-19 , Epidemias , China , Humanos , Unidades Móveis de Saúde , Isolamento de Pacientes , SARS-CoV-2RESUMO
In contrast to the plasma membrane, the vacuole membrane has not yet been associated with electrical excitation of plants. Here, we show that mesophyll vacuoles from Arabidopsis sense and control the membrane potential essentially via the K+-permeable TPC1 and TPK channels. Electrical stimuli elicit transient depolarization of the vacuole membrane that can last for seconds. Electrical excitability is suppressed by increased vacuolar Ca2+ levels. In comparison to wild type, vacuoles from the fou2 mutant, harboring TPC1 channels insensitive to luminal Ca2+, can be excited fully by even weak electrical stimuli. The TPC1-loss-of-function mutant tpc1-2 does not respond to electrical stimulation at all, and the loss of TPK1/TPK3-mediated K+ transport affects the duration of TPC1-dependent membrane depolarization. In combination with mathematical modeling, these results show that the vacuolar K+-conducting TPC1 and TPK1/TPK3 channels act in concert to provide for Ca2+- and voltage-induced electrical excitability to the central organelle of plant cells.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Canais de Cálcio/metabolismo , Potenciais da Membrana/fisiologia , Vacúolos/fisiologia , Proteínas de Arabidopsis/genética , Canais de Cálcio/genética , Sinalização do Cálcio/fisiologia , Membranas Intracelulares/fisiologia , Mutação com Perda de Função , Células do Mesofilo/citologia , Células do Mesofilo/fisiologia , Plantas Geneticamente Modificadas , Potássio/metabolismo , Canais de Potássio/metabolismo , Canais de Potássio de Domínios Poros em Tandem/metabolismoRESUMO
Nuclear factor-erythroid 2-related factor 3 (NRF3), a nuclear transcription factor, has been implicated in various cellular processes including carcinogenesis. However, mechanisms underlying its regulation in carcinogenesis are unclear. Herein, we found that NRF3 is lowly expressed in colorectal cancer (CRC) tissues and cells, and NRF3 low-expressions in CRC tissue samples are associated with CRC carcinogenesis and poor patient outcomes. Nrf3-knockdown increased CRC cell growth, colony formation, and cell motility and invasion, and Nrf3-knockin dramatically decreased CRC cell growth and colony formation. Mechanistically, NRF3 increased CRC cell apoptosis and arrested cell G2/M stage. NRF3 was found to be reversely with epidermal growth factor receptor (EGFR) and p38. Strikingly, Nrf3-knockin dramatically decreased phosphorylated-EGFR at Tyrosine845 (pEGFR Tyr845) and phosphorylated-p38 at Threonine180/Tyrosine182 (p-p38 Thr180/Tyr182) expressions, and Nrf3-knockdown increased pEGFR Tyr845 and p-p38 Thr180/Tyr182. Moreover, NRF3 regulated EGFR and p38 down-stream molecules, protein kinase B (AKT), activating transcription factor (ATF) 2, and C/EBP homologous protein (CHOP) expressions. NRF3 loss-increased CRC growth through EGFR and p38 was confirmed in nude mice. Collectively, NRF3-loss in CRC cell increases EGFR and p38 phosphorylation activation, enhances cell proliferation and decreases cell apoptosis, and finally promotes CRC malignance.
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Molecule interacting with CasL2 (MICAL2), a microtubule-associated monooxygenase, is highly expressed in various cancers and is involved in cancer pathogenesis, but the mechanisms underlying its regulation in carcinogenesis are unclear. In this study, we aim to clarify the mechanism by which MICAL2 participates in colorectal cancer (CRC) and identify novel markers for predicting prognosis of CRC patients. Methods: The value of MICAL2 in CRC prognosis was determined by immunohistochemical analysis of a CRC biopsy array. A short hairpin RNA target MICAL2 (shMICAL2) was designed to knock down MICAL2 expression and observe MICAL2's function on CRC cell growth. mRNA expression array was used to screen target molecules of MICAL2. HCT116 p53+/+ and HCT116 p53-/- cells were used to confirm whether MICAL2 exerts its oncogenic effect through p53. The in vivo effect of MICAL2 on CRC growth was assessed by subcutaneously injecting MICAL2-knockout CRC cells into the dorsal flank of each mouse. Immunofluorescence was used to observe the effect of MICAL2 on p53 cellular location. Reverse-phase nano ESI-LCMS analysis was used to investigate if MICAL2 mediates p53 oxidation. Results: MICAL2 was found to be highly expressed in CRC tissues, and its expression was associated with CRC carcinogenesis and poor patient outcome. MICAL2-knockdown decreased growth and colony formation of CRC cells, which was linked with cell cycle arrest and apoptosis. MICAL2 physically interacted with p53 and retained p53 in the cytoplasm. MICAL2 shortened the half-life of p53, and ectopic MICAL2 expression decreased p53 protein stability through ubiquitin degradation. MICAL2 was also found to oxidize p53 at methionine 40 and 160, which mediated p53 ubiquitin degradation. MICAL2-promoted CRC growth in vivo was confirmed in nude mice. Conclusion: MICAL2 binds to p53, retains p53 in the cytoplasm and oxidizes it at Met 40 and 160, promotes p53 ubiquitination, and decreases p53 function. MICAL2-reduced p53 promotes CRC development.
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Neoplasias Colorretais/patologia , Metionina/metabolismo , Proteínas dos Microfilamentos/análise , Oxirredutases/análise , Processamento de Proteína Pós-Traducional , Proteólise , Proteína Supressora de Tumor p53/metabolismo , Adulto , Idoso , Animais , Biópsia , Carcinogênese , Proliferação de Células , Cromatografia Líquida , Modelos Animais de Doenças , Feminino , Técnicas de Silenciamento de Genes , Técnicas de Inativação de Genes , Células HCT116 , Xenoenxertos , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Nus , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Pessoa de Meia-Idade , Transplante de Neoplasias , Oxirredução , Oxirredutases/genética , Oxirredutases/metabolismo , Ligação Proteica , Espectrometria de Massas por Ionização por Electrospray , UbiquitinaçãoRESUMO
BACKGROUND: MNAT1 (menage a trois 1, MAT1), a cyclin-dependent kinase-activating kinase (CAK) complex, high expresses in various cancers and is involved in cancer pathogenesis. However, mechanisms underlying its regulation in carcinogenesis are unclear. METHODS: The tissue microarray of colorectal cancer (CRC) was used to evaluate MNAT1 expressions in CRC tissues using immunohistochemistry, CRC cell lines were also detected MNAT1 expression using Western-blotting. MNAT1 and shMNAT1 vectors were constructed, and transfected into CRC cells. Cell growths of the transfected cells were observed using MTT and colony formation. The affects of MNAT1 on p53 expression were analyzed using Western-blotting and Real-time PCR. Immunoprecipitation assay was used to analyze the interaction p53 and MNAT1, and Western-blotting was used to test the effects of MNAT1 on p53 downstream molecules. The apoptosis of CRC cells with MNAT1 or shMNAT1 were analyzed using flow cytometry. BABL/c athymic nude mice were used to observe the effect of MNAT1 on CRC cell growth in vivo. RESULTS: MNAT1 was found to be overexpressed in CRC tissues and cells, and MNAT1 expressions in CRC tissue samples were associated with CRC carcinogenesis and poor patient outcomes. MNAT1-knockin increased CRC cell growth and colony formation, and MNAT1-knockdown dramatically decreased cell motility and invasion. MNAT1 physically interacted with p53, MNAT1 also increased the interaction of MDM2 with p53. Strikingly, MNAT1 mediated p53 ubiquitin-degradation. MNAT1 shortened p53 half-life, and ectopic MNAT1 expression decreased p53 protein stability. Moreover, MNAT1 induced RAD51 and reduced p21, cleaved-caspase3, cleaved-PARP and BAX expression. MNAT1 inhibited CRC cell apoptosis. shMANT1 decreased tumor growths in nude mice following p53 increase. CONCLUSION: MNAT1 binds to p53, mediates p53 ubiquitin-degradation through MDM2, increases cell growth and decreases cell apoptosis, and finally promotes CRC malignance. MNAT1 binding to p53 and mediating p53 ubiquitin-degradation axis represents a novel molecular joint in the p53 pathway.