Piao Yongjun, Lee Seong Keon, Lee Eun-Joon, Robertson Keith D, Shi Huidong, Ryu Keun Ho, Choi Jeong-Hyeon
Cancer Center, Georgia Regents University, Augusta, GA, USA.
College of Electrical and Computer Engineering, Chungbuk National University, Cheongju, Republic of Korea.
Bioinformatics. 2017 Apr 15;33(8):1139-1146. doi: 10.1093/bioinformatics/btw785.
Chromatin accessibility plays a key role in epigenetic regulation of gene activation and silencing. Open chromatin regions allow regulatory elements such as transcription factors and polymerases to bind for gene expression while closed chromatin regions prevent the activity of transcriptional machinery. Recently, Methyltransferase Accessibility Protocol for individual templates-Bisulfite Genome Sequencing (MAPit-BGS) and nucleosome occupancy and methylome sequencing (NOMe-seq) have been developed for simultaneously profiling chromatin accessibility and DNA methylation on single molecules. Therefore, there is a great demand in developing computational methods to identify chromatin accessibility from MAPit-BGS and NOMe-seq.
In this article, we present CAME (Chromatin Accessibility and Methylation), a seed-extension based approach that identifies chromatin accessibility from NOMe-seq. The efficiency and effectiveness of CAME were demonstrated through comparisons with other existing techniques on both simulated and real data, and the results show that our method not only can precisely identify chromatin accessibility but also outperforms other methods.
CAME is implemented in java and the program is freely available online at http://sourceforge.net/projects/came/.
jechoi@gru.edu or khryu@dblab.chungbuk.ac.kr.
Supplementary data are available at Bioinformatics online.
染色质可及性在基因激活和沉默的表观遗传调控中起关键作用。开放染色质区域允许转录因子和聚合酶等调控元件结合以进行基因表达,而封闭染色质区域则阻止转录机制的活性。最近,已开发出用于单个模板的甲基转移酶可及性协议-亚硫酸氢盐基因组测序(MAPit-BGS)和核小体占有率与甲基化组测序(NOMe-seq),用于在单分子上同时分析染色质可及性和DNA甲基化。因此,迫切需要开发计算方法以从MAPit-BGS和NOMe-seq中识别染色质可及性。
在本文中,我们提出了CAME(染色质可及性与甲基化),这是一种基于种子扩展的方法,可从NOMe-seq中识别染色质可及性。通过在模拟数据和真实数据上与其他现有技术进行比较,证明了CAME的效率和有效性,结果表明我们的方法不仅可以精确识别染色质可及性,而且优于其他方法。
CAME用Java实现,程序可在http://sourceforge.net/projects/came/上免费在线获取。
jechoi@gru.edu或khryu@dblab.chungbuk.ac.kr。
补充数据可在《生物信息学》在线获取。