基于转录调控模体的人不同组织基因差异性的统计分析

Statistical analysis on differences of human specific tissue genes based on transcriptional

转录调控是基因表达调控的主要过程,而转录调控模体使用的差异性可能是导致基因组织特异性的因素之一。本文提出一种不同组织基因调控差异性的统计分析方法,首先结合泊松分布和主成分分析提取基因启动子中过表达模体作为潜在的转录因子结合位点。基于这些位点通过Wilcoxon秩和检验获得不同组织基因结构的差异性。再用超几何分布确定出现次数显著的模体作为组织基因的特有模体,并分析特有模体的碱基特征及在启动子序列中的位置分布。将特有模体与TRANSFAC数据库进行对照,得到潜在的调控组织特异性基因的转录因子结合位点。以人管家基因及30个组织特异性基因为分析对象,得到不同组织调控模体使用的差异性信息。

Transcriptional regulation is the main regulatory process by gene expression. The differences in the use of transcriptional regulatory motifs may be one of the factors leading to gene tissue specificity. This paper presents a statistical method for analysis of the regulatory differences between different tissue genes. Firstly, over-represented motifs in gene promoters were extracted as potential transcription factor binding sites based on Poisson distribution and principal components analysis. Based on these sites, differences of gene structures in different tissues were obtained based on Wilcoxon rank sum test. Then, over-represented motifs were determined as specific motifs for certain tissue genes based on hypergeometrie distribution, and the distribution and characteristics of these specific motifs in the promoter sequences were analyzed. By comparing these specific motifs with TRANSFAC database, the potential transcription factor binding sites in tissue-specific genes were selected. Finally, housekeeping genes and 30 tissue-specific genes were analyzed and the use differences of regulatory motifs in different tissues were found out.