对包含miR449的Rb-E2F路径的动力学行为的研究

发布时间：2017-12-31 03:35

本文关键词：对包含miR449的Rb-E2F路径的动力学行为的研究　出处：《郑州大学》2016年硕士论文　论文类型：学位论文

更多相关文章：噪声 随机共振 miR449 时滞 Hopf分岔

【摘要】：实验研究表明microRNAs(miRNAs)在调节基因网络方面起着重要作用,它们能同时调节多种基因的表达来协调整个细胞进程,在癌细胞中,恢复miRNAs到正常水平能够逆转异常的细胞生长,因此,了解怎样控制癌细胞中miRNAs的正常水平成为控制癌症的关键步骤.本文中,我们提出了一种控制niRNA水平的方法,研究了包含miRNA (miR449)的基因调控网络Rb-E2F路径.一方面,通过建立数学模型,我们研究了噪声对Rb-E2F路径的动力学行为的影响,发现了噪声强度和系统响应之间存在一定的关系,并定义了随机共振现象,我们发现可以通过最佳噪声强度来控制随机共振,证明了miRNA的水平是可控的,这些发现很可能为治愈癌症提供一种新的思路.另一方面,通过建立另一个数学模型,我们研究了时滞对Rb-E2F路径的动力学行为的影响,我们发现在一定条件下,对于所有的时间延迟,时滞系统的平衡态都是稳定的；在另外的条件下,存在一个时滞临界值,当时滞小于这个临界值时,平衡态是稳定的,当时滞大于这个临界值时,平衡态变得不再稳定,于是当时滞穿过时滞临界值的过程中,Hopf分岔现象出现.我们还通过数值模拟证明了理论结果.
[Abstract]:MicroRNAsmiRNAss play an important role in the regulation of gene network, they can regulate the expression of many genes simultaneously to coordinate the whole cell process, in cancer cells. Restoring miRNAs to normal levels can reverse abnormal cell growth, so understanding how to control normal levels of miRNAs in cancer cells is a key step in cancer control. We propose a method to control the level of niRNA and study the Rb-E2F path of gene regulatory network including miRNA miR449. On the one hand, we establish a mathematical model. We study the effect of noise on the dynamic behavior of Rb-E2F path, find that there is a certain relationship between the noise intensity and the system response, and define the stochastic resonance phenomenon. We have found that stochastic resonance can be controlled by optimal noise intensity, which proves that the level of miRNA is controllable. These findings may provide a new way to cure cancer, on the other hand. By establishing another mathematical model, we study the effect of time delay on the dynamic behavior of Rb-E2F path. We find that under certain conditions, for all time delays. The equilibrium states of time-delay systems are stable. Under other conditions, the equilibrium state is stable when the hysteresis is less than this critical value, and when the hysteresis is larger than this critical value, the equilibrium state becomes unsteady. Then Hopf bifurcation appears in the process of passing through the critical value of time delay at that time, and the theoretical results are proved by numerical simulation.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：R730.2;O175;Q811.4

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