人类CD4^+T细胞核小体定位模式及其与TFBS分布特征关系研究

Genome-wide nucleosome positioning mode and relationship with TFBS distribution in human CD4^+T cell

目的研究人类CD4+T细胞全基因组核小体抑制和激活状态下的定位模式,转录因子结合位点(Transcription factor binding site,TFBS)分布特征以及两者之间的关系。方法采用生物信息学软件R、Java等通过编写比对算法进行统计学分析。结果人类CD4+T细胞中核小体定位在染色质上的分布比例为0.6,从休眠到激活状态核小体定位发生位置改变,呈现稳定定位模式和动态定位模式,且比例分别为2%和98%,核小体定位具有较大的动态变化性;核小体定位与TFBS位置关系研究中,发现分布在核小体内的TFBS数目较大,但总体长度较短;而分布在连接DNA上的TFBS数目相对较少,但总体长度较长。结论人类CD4+T细胞休眠和激活状态下全基因组的核小体定位模式基本一致,核小体定位与TFBS关系有明显特征。

Objective To study the human genome-wide nucleosome positioning mode from CD4＋ T cell under inhibition and activation status, TFBS distribution characteristics as well as the relationship between them. Methods Using bioinformatics software R, Java to write align- ment algorithms to perform statistical analysis. Results The nucleosomes positioning rate on the chromatin in human CD4 ＋ T cell was about 60%. Nucleosome positioning lacation came to change when condition of cell was from rest condition to activity condition, both stable positio- ning mode and dynamic positioning mode, and the proportion of them in all of nueleosome posi- tioning were 2% and 98% respectively. Nucleosome positioning appeared larger dynamic varia- bility. Studying the position relationship between nucleosome positioning and TFBS, found that the distribution number of TFBS in nucleosome positioning sequences was bigger, but the over- all length was shorter. And distribution number in the linker was relatively small, but the over- all length was longer than the other. Conclusion The distribution of genome-wide nucleosomepositioning in Human CD4 ＋ T cells is basically consistent under rest and activate cell state. The relationship between nucleosome positioning and TFBS has obvious characteristics.