Nguyen Nha, Vo An, Choi Inchan, Won Kyoung-Jae
1 Department of Genetics, School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania.
J Comput Biol. 2015 Mar;22(3):236-49. doi: 10.1089/cmb.2014.0221. Epub 2014 Nov 10.
Studying epigenetic landscapes is important to understand the condition for gene regulation. Clustering is a useful approach to study epigenetic landscapes by grouping genes based on their epigenetic conditions. However, classical clustering approaches that often use a representative value of the signals in a fixed-sized window do not fully use the information written in the epigenetic landscapes. Clustering approaches to maximize the information of the epigenetic signals are necessary for better understanding gene regulatory environments. For effective clustering of multidimensional epigenetic signals, we developed a method called Dewer, which uses the entropy of stationary wavelet of epigenetic signals inside enriched regions for gene clustering. Interestingly, the gene expression levels were highly correlated with the entropy levels of epigenetic signals. Dewer separates genes better than a window-based approach in the assessment using gene expression and achieved a correlation coefficient above 0.9 without using any training procedure. Our results show that the changes of the epigenetic signals are useful to study gene regulation.
研究表观遗传景观对于理解基因调控的条件很重要。聚类是一种通过根据基因的表观遗传条件对基因进行分组来研究表观遗传景观的有用方法。然而,经典的聚类方法通常在固定大小的窗口中使用信号的代表性值,并未充分利用表观遗传景观中所蕴含的信息。为了更好地理解基因调控环境,需要采用能够最大化表观遗传信号信息的聚类方法。为了对多维表观遗传信号进行有效聚类,我们开发了一种名为Dewer的方法,该方法利用富集区域内表观遗传信号的平稳小波熵进行基因聚类。有趣的是,基因表达水平与表观遗传信号的熵水平高度相关。在使用基因表达进行的评估中,Dewer比基于窗口的方法能更好地分离基因,并且在不使用任何训练过程的情况下实现了高于0.9的相关系数。我们的结果表明,表观遗传信号的变化对于研究基因调控是有用的。