Objective This work examines the impact of external electric fields at terahertz(THz)frequencies on doublestranded deoxyribonucleic acid(dsDNA)systems adsorbed on Au(111)surfaces in aqueous environments.Methods The in...Objective This work examines the impact of external electric fields at terahertz(THz)frequencies on doublestranded deoxyribonucleic acid(dsDNA)systems adsorbed on Au(111)surfaces in aqueous environments.Methods The investigation utilizes a molecular dynamics(MD)approach at the atomic level and vibrational dynamics calculations using the GolDNA-Amber force field.Results The results reveal that the sugar-phosphate backbone of the DNA exhibits reduced adherence to the gold surface,while the side chains display a stronger affinity.When subjecting the hydrated DNA strands to an electric field with frequencies up to 10 THz,peak intensities of vibrational dynamic density(VDoS)are observed at five different frequencies.Moreover,the strong electric field causes hydrogen bonds in the DNA within the slit to break.The sensitivity to the electric field is particularly pronounced at 8.8 THz and 9.6 THz,with different vibrational modes observed at varying electric field strengths.Conclusion These findings contribute to an enhanced understanding of the molecular organization of gold-plated charged biological interfaces.展开更多
Kinesin-1 motor protein is a homodimer containing two identical motor domains connected by a common long coiledcoil stalk via two flexible neck linkers. The motor can step on a microtubule with a velocity of about 1 ...Kinesin-1 motor protein is a homodimer containing two identical motor domains connected by a common long coiledcoil stalk via two flexible neck linkers. The motor can step on a microtubule with a velocity of about 1 μm·s-1and an attachment duration of about 1 s under physiological conditions. The available experimental data indicate a tradeoff between velocity and attachment duration under various experimental conditions, such as variation of the solution temperature,variation of the strain between the two motor domains, and so on. However, the underlying mechanism of the tradeoff is unknown. Here, the mechanism is explained by a theoretical study of the dynamics of the motor under various experimental conditions, reproducing quantitatively the available experimental data and providing additional predictions. How the various experimental conditions lead to different decreasing rates of attachment duration versus velocity is also explained.展开更多
文摘结肠癌是世界上第三大诊断癌症,也是癌症相关死亡的第二大原因。随着生物技术的不断发展,人们发现长链非编码RNA(long non-coding RNA,lncRNA)和铁死亡在结肠癌的预后中起着重要的作用。因此,研究铁死亡与lncRNA之间的关系将对改善结肠癌患者的预后生存有所帮助。本文筛选了结肠癌组织和正常组织中差异表达的铁死亡相关基因,并进行GO(Gene ontology)和KEGG(Kyoto encyclopedia of genes and genomes)富集分析。筛选出与结肠癌预后相关的铁死亡相关lncRNA,通过LASSO分析构建了基于5个lncRNA基因的预后模型。将结肠癌样本分为高、低风险组,对该模型进行KM(Kaplan-meier)生存分析和ROC分析,KM分析结果显示高风险组的预后较差;ROC结果表明,该模型能较好地预测结肠癌的生存。本文构建的基于铁死亡相关lncRNA的预后模型可以准确预测结肠癌患者的预后状态,这为结肠癌的预后和治疗提供了一定的理论依据。
文摘Objective This work examines the impact of external electric fields at terahertz(THz)frequencies on doublestranded deoxyribonucleic acid(dsDNA)systems adsorbed on Au(111)surfaces in aqueous environments.Methods The investigation utilizes a molecular dynamics(MD)approach at the atomic level and vibrational dynamics calculations using the GolDNA-Amber force field.Results The results reveal that the sugar-phosphate backbone of the DNA exhibits reduced adherence to the gold surface,while the side chains display a stronger affinity.When subjecting the hydrated DNA strands to an electric field with frequencies up to 10 THz,peak intensities of vibrational dynamic density(VDoS)are observed at five different frequencies.Moreover,the strong electric field causes hydrogen bonds in the DNA within the slit to break.The sensitivity to the electric field is particularly pronounced at 8.8 THz and 9.6 THz,with different vibrational modes observed at varying electric field strengths.Conclusion These findings contribute to an enhanced understanding of the molecular organization of gold-plated charged biological interfaces.
文摘Kinesin-1 motor protein is a homodimer containing two identical motor domains connected by a common long coiledcoil stalk via two flexible neck linkers. The motor can step on a microtubule with a velocity of about 1 μm·s-1and an attachment duration of about 1 s under physiological conditions. The available experimental data indicate a tradeoff between velocity and attachment duration under various experimental conditions, such as variation of the solution temperature,variation of the strain between the two motor domains, and so on. However, the underlying mechanism of the tradeoff is unknown. Here, the mechanism is explained by a theoretical study of the dynamics of the motor under various experimental conditions, reproducing quantitatively the available experimental data and providing additional predictions. How the various experimental conditions lead to different decreasing rates of attachment duration versus velocity is also explained.
