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1.
Int J Biol Macromol ; 264(Pt 2): 130691, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38458293

RESUMEN

Given their outstanding efficiency and selectivity, enzymes are integral in various domains such as drug synthesis, the food industry, and environmental management. However, the inherent instability of natural enzymes limits their widespread industrial application. In this study, we underscore the efficacy of enhancing protein thermal stability through comprehensive protein design strategies, encompassing elements such as the free energy of protein folding, internal forces within proteins, and the overall structural design. We also demonstrate the efficiency and precision of combinatorial screening in the thermal stability design of aldo-keto reductase (AKR7-2-1). In our research, three single-point mutations and five combinatorial mutations were strategically introduced into AKR7-2-1, using multiple computational techniques. Notably, the E12I/S235I mutant showed a significant increase of 25.4 °C in its melting temperature (Tm). Furthermore, the optimal mutant, E12V/S235I, maintained 80 % of its activity while realizing a 16.8 °C elevation in Tm. Remarkably, its half-life at 50 °C was increased to twenty times that of the wild type. Structural analysis indicates that this enhanced thermal stability primarily arises from reduced oscillation in the loop region and increased internal hydrogen bonding. The promising results achieved with AKR7-2-1 demonstrate that our strategy could serve as a valuable reference for enhancing the thermal stability of other industrial enzymes.


Asunto(s)
Mutación Puntual , Aldo-Ceto Reductasas/genética , Temperatura , Estabilidad Proteica , Mutación , Estabilidad de Enzimas
2.
Anim Biotechnol ; 35(1): 2299944, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38164963

RESUMEN

Cattle are sensitive to temperature fluctuations but adapt well to inclement weather conditions. When environmental temperatures exceed specific thresholds, heat stress becomes a critical concern for cattle. The TRPM2 gene, which resides on cattle chromosome 1 encodes a TRP channel protein, holding a unique capacity to sense temperature changes and facilitate rapid response to avoid heat stress. Here, we utilized the Bovine Genome Variation Database (BGVD) (http://animal.omics.pro/code/index.php/BosVar), and identified a missense mutation site, c.805A > G: p. Met269Val (rs527146862), within the TRPM2 gene. To elucidate the functional assessment of this mutation in temperature adaptation attributes of Chinese cattle, we genotyped 407 samples from 20 distinct breeds representing diverse climatic zones across China. The association analysis incorporates three temperature parameters and revealed compelling insights in terms of allele frequency. Interestingly, the prevalence of the wild-type allele A was notably higher among northern cattle breeds and this trend diminished gradually as observed in southern cattle populations. Conversely, the mutant-type allele G demonstrated a contrasting trend. Moreover, southern cattle exhibited markedly higher frequencies of GG and GA genotypes (P < 0.01). The presence of heterozygous and homozygous mutations appears to confer an enhanced capacity for adaptation to elevated temperatures. These results provide unequivocal correlation evidence between TRPM2 genotypes (AA, GA, GG) and environmental temperature parameters and comprehend the genetic mechanisms governing temperature adaptation in cattle. This provides valuable insights for strategic breed selection across diverse climatic regions, thereby aiding livestock production amid evolving climate challenges.


The TRPM2 gene encodes TRP channel protein that helps animals in combating heat stress. Twenty Chinese local cattle breeds were genotyped, and association analysis was performed. This investigation encompasses the distribution pattern of the missense mutation locus rs527146862 of the TRPM2 gene in southern, northern, and central cattle populations. The results demonstrated a significant relationship between rs527146862 locus and temperature adaptation attributes in Chinese cattle.


Asunto(s)
Canales Catiónicos TRPM , Bovinos/genética , Animales , Temperatura , Canales Catiónicos TRPM/genética , Frecuencia de los Genes , Genotipo , Mutación Missense , Polimorfismo de Nucleótido Simple
4.
Front Med ; 17(3): 476-492, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36973570

RESUMEN

tRNA-derived small RNAs (tsRNAs) are novel non-coding RNAs that are involved in the occurrence and progression of diverse diseases. However, their exact presence and function in hepatocellular carcinoma (HCC) remain unclear. Here, differentially expressed tsRNAs in HCC were profiled. A novel tsRNA, tRNAGln-TTG derived 5'-tiRNA-Gln, is significantly downregulated, and its expression level is correlated with progression in patients. In HCC cells, 5'-tiRNA-Gln overexpression impaired the proliferation, migration, and invasion in vitro and in vivo, while 5'-tiRNA-Gln knockdown yielded opposite results. 5'-tiRNA-Gln exerted its function by binding eukaryotic initiation factor 4A-I (EIF4A1), which unwinds complex RNA secondary structures during translation initiation, causing the partial inhibition of translation. The suppressed downregulated proteins include ARAF, MEK1/2 and STAT3, causing the impaired signaling pathway related to HCC progression. Furthermore, based on the construction of a mutant 5'-tiRNA-Gln, the sequence of forming intramolecular G-quadruplex structure is crucial for 5'-tiRNA-Gln to strongly bind EIF4A1 and repress translation. Clinically, 5'-tiRNA-Gln expression level is negatively correlated with ARAF, MEK1/2, and STAT3 in HCC tissues. Collectively, these findings reveal that 5'-tiRJNA-Gln interacts with EIF4A1 to reduce related mRNA binding through the intramolecular G-quadruplex structure, and this process partially inhibits translation and HCC progression.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Factor 4A Eucariótico de Iniciación/genética , Línea Celular , ARN de Transferencia/química , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , ARN , Proliferación Celular
5.
Cancer Sci ; 113(10): 3476-3488, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35879647

RESUMEN

Transfer RNA-derived fragments are a group of small noncoding single-stranded RNA that play essential roles in multiple diseases. However, their biological functions in carcinogenesis are not well understood. In this study, 5'tRF-Gly was found to have significantly high expression in hepatocellular carcinoma (HCC), and the upregulation of 5'tRF-Gly was positively correlated with tumor size and tumor metastasis. Overexpression of 5'tRF-Gly induced increased growth rate and metastasis in HCC cells in vitro and in nude mice, while knockdown showed the opposite effect. Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) was confirmed to be a direct target of 5'tRF-Gly in HCC. In addition, the cytological effect of CEACAM1 knockdown proved to be similar to the overexpression of 5'tRF-Gly. Moreover, attenuation of CEACAM1 expression rescued the 5'tRF-Gly-mediated promoting effects on HCC cells. These data show that 5'tRF-Gly is a new tumor-promoting factor and could be a potential diagnostic biomarker or new therapeutic target for HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , ARN Largo no Codificante , Animales , Antígenos CD , Antígeno Carcinoembrionario/genética , Antígeno Carcinoembrionario/metabolismo , Carcinoma Hepatocelular/patología , Molécula 1 de Adhesión Celular/metabolismo , Moléculas de Adhesión Celular , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/patología , Ratones , Ratones Desnudos , ARN , ARN Largo no Codificante/genética , ARN de Transferencia
6.
Biomed Res Int ; 2019: 9828637, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31886273

RESUMEN

To precisely predict the clinical outcome and determine the optimal treatment options for patients with esophageal squamous cell carcinoma (ESCC) remains challenging. Prognostic models based on multiple molecular markers of tumors have been shown to have superiority over the use of single biomarkers. Our previous studies have identified the crucial role of ezrin in ESCC progression, which prompted us to hypothesize that ezrin-associated proteins contribute to the pathobiology of ESCC. Herein, we explored the clinical value of a molecular model constructed based on ezrin-associated proteins in ESCC patients. We revealed that the ezrin-associated proteins (MYC, PDIA3, and ITGA5B1) correlated with the overall survival (OS) and disease-free survival (DFS) of patients with ESCC. High expression of MYC was associated with advanced pTNM-stage (P=0.011), and PDIA3 and ITGA5B1 were correlated with both lymph node metastasis (PDIA3: P < 0.001; ITGA5B1: P=0.001) and pTNM-stage (PDIA3: P=0.001; ITGA5B1: P=0.009). Furthermore, we found that, compared with the current TNM staging system, the molecular model elicited from the expression of MYC, PDIA3, and ITGA5B1 shows higher accuracy in predicting OS (P < 0.001) or DFS (P < 0.001) in ESCC patients. Moreover, ROC and regression analysis demonstrated that this model was an independent predictor for OS and DFS, which could also help determine a subgroup of ESCC patients that may benefit from chemoradiotherapy. In conclusion, our study has identified a novel molecular prognosis model, which may serve as a complement for current clinical risk stratification approaches and provide potential therapeutic targets for ESCC treatment.


Asunto(s)
Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/genética , Modelos Genéticos , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas de Esófago/diagnóstico , Carcinoma de Células Escamosas de Esófago/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Valor Predictivo de las Pruebas , Pronóstico
7.
Br J Cancer ; 118(11): 1476-1484, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29765149

RESUMEN

BACKGROUND: Oesophageal squamous cell carcinoma (ESCC) is one of the most malignant cancers worldwide. Treatment of ESCC is in progress through accurate staging and risk assessment of patients. The emergence of potential molecular markers inspired us to construct novel staging systems with better accuracy by incorporating molecular markers. METHODS: We measured H scores of 23 protein markers and analysed eight clinical factors of 77 ESCC patients in a training set, from which we identified an optimal MASAN (MYC, ANO1, SLC52A3, Age and N-stage) signature. We constructed MASAN models using Cox PH models, and created MASAN-staging systems based on k-means clustering and minimum-distance classifier. MASAN was validated in a test set (n = 77) and an independent validation set (n = 150). RESULTS: MASAN possessed high predictive accuracies and stratified ESCC patients into three prognostic groups that were more accurate than the current pTNM-staging system for both overall survival and disease-free survival. To facilitate clinical utilisation, we also constructed MASAN-SI staging systems based on staining indices (SI) of protein markers, which possessed similar prognostic performance as MASAN. CONCLUSION: MASAN provides a good alternative staging system for ESCC prognosis with a high precision using a simple model.


Asunto(s)
Anoctamina-1/metabolismo , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/patología , Proteínas de Transporte de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Factores de Edad , Algoritmos , Biomarcadores de Tumor/metabolismo , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas de Esófago/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Sensibilidad y Especificidad , Análisis de Supervivencia , Análisis de Matrices Tisulares
8.
Zhonghua Nan Ke Xue ; 16(7): 579-83, 2010 Jul.
Artículo en Chino | MEDLINE | ID: mdl-20873588

RESUMEN

Phimosis and redundant prepuce, as common problems in andrology, are found in the majority of male neonates. Early treatment of neonatal phimosis and redundant prepuce has the advantages of better cost--effectiveness and higher safety, and contributes much to the prevention of childhood urinary tract infection and adult sexually transmitted diseases, as well as to the improvement of genital hygiene. Neonatal circumcision is commonly performed in some countries, but remains at a low rate in China. This article updates surgical and non-surgical treatments of neonatal phimosis and redundant prepuce, introduces the benefits of neonatal circumcision, and appeals for more attention to the management of neonatal phimosis and redundant prepuce.


Asunto(s)
Circuncisión Masculina/métodos , Fimosis/cirugía , Fimosis/terapia , Preescolar , Humanos , Lactante , Masculino
9.
Zhonghua Nan Ke Xue ; 15(5): 395-402, 2009 May.
Artículo en Chino | MEDLINE | ID: mdl-19514549

RESUMEN

Recent randomized controlled clinical trials in Africa have demonstrated that adult male circumcision (MC) efficiently decreases the rate of HIV, HPV and HSV-2 infections. Many studies have clearly shown that MC is a simple, safe, and cost-effective method for the prevention of sexually transmitted diseases and urinary tract infection, and for improving genital hygiene. While a 30% MC prevalence exists worldwide, only 5% or less of the Chinese males have undergone circumcision. In this review, we report recent trends in international MC and HIV prevention efforts, as well as the potential benefits and importance of promoting MC in China. We appeal to medical and public health authorities to pay close attention to the international experience in MC and HIV prevention.


Asunto(s)
Circuncisión Masculina , Infecciones por VIH/prevención & control , Enfermedades de Transmisión Sexual/prevención & control , Humanos , Masculino , Medicina Reproductiva
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