原核生物基因组复制起始点识别和结构的分析.pdf

河北工业大学硕士学位论文- i - 原核生物基因组复制起始点的识别与结构分析摘要 随着测序技术的飞速发展和越来越多的全基因组序列被测序完成,如何从海量的数据中提取有用的信息就变得极其重要。复制起始区域的识别是生物信息学关注的热点之一。本论文基于在细菌复制起始点两侧碱基组分的差异,提出识别复制起始点的双组分的窗口模型。通过窗口沿着基因组的DNA 链滑动,得到两组描述组分变化的曲线。利用小波分析技术对两组曲线进行去噪处理,找出曲线之交点, 进而确定原核基因组的复制起始点位置。论文第一章主要阐述生物信息学的发展背景及主要研究内容,并简单介绍人类基因组和模式生物基因组计划。 论文第二章重点介绍论文中涉及的生物学背景知识,阐明了原核生物染色体复制机制。 论文第三章主要介绍小波变换的有关知识。小波分析是解决信号消噪问题的十分有效的工具。论文中重点介绍了该方法常用的小波函数以及对信号进行小波消噪的步骤。论文第四章着重介绍用双组分的窗口模型结合小波分析技术识别原核生物基因组复制起始点并对得到的结果做出相应的讨论。从得到的结果来看,原核生物基因组复制起始点分布在两条G+T 和A+C 含量变化趋势曲线交点附近。多数原核生物基因组在复制起始点附近G+T 的含量从局部最小变为最大, A+C 的含量从局部最小变为最大,只有少数基因组情况相反。 论文第五章重点介绍分子马达蛋白数据库的构建过程。 关键词: 原核生物,基因组,染色体,复制起始点,小波函数,小波分析原核生物基因组复制起始点的识别与结构分析- ii - IDENTIFICATION OF REPLICATION ORIGINS AND ANALYSIS OF ST RUCTURES IN PROKARYOTE GENOMES ABSTRACT With the implementation of a large scale of genome sequence project, a large number of sequences of prokaryotic and anisms have been plished. It is very important to analyze the sequences at gene and genome le vels. Identification of replication origination regions is one of the hotspots in bioinformatic s field. In this thesis , window model of double components is proposed to identify replication or igins based on the difference of ponent flanked by bacteria replication or igins. Getting two sets of curv es ponent varieties by the slide of window along DNA st rand in genome. Using the techno logy of wavelet analysis to denoise for two sets of curves, to find the point of intersection of these tw o curves and make sure the replication origins pos ition in prokaryote genome. In chapter , what is the bioinformatics is introduced, and the main wo Ⅰ rk of this field is represented. Moreover what is th e human genome and model biology genome project is also introduced. In chapter , knowledge of biology related to this study is expla Ⅱ ined, and the replication mechanism of prokaryote genome is illuminated. In chapter , Ⅲ knowledge about wavelet transform is intr oduced. Wavelet analysis is a quite