ChIP-AP: An Integrated Analysis Pipeline for Unbiased ChIP-seq Analysis. (Brief Bioinform, Jan 2022)

Jeremiah Suryatenggara 1Kol Jia Yong 1 2Danielle E Tenen 3Daniel G Tenen 1 4Mahmoud A Bassal 1 4

Affiliations

1Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore.
2Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Singapore.
3Broad Institute of MIT and Harvard, Boston, 02142, USA.
4Harvard Stem Cell Institute, Boston, 02138, USA.

Abstract

Chromatin immunoprecipitation coupled with sequencing (ChIP-seq) is a technique used to identify protein-DNA interaction sites through antibody pull-down, sequencing and analysis; with enrichment ‘peak’ calling being the most critical analytical step. Benchmarking studies have consistently shown that peak callers have distinct selectivity and specificity characteristics that are not additive and seldom completely overlap in many scenarios, even after parameter optimization. We therefore developed ChIP-AP, an integrated ChIP-seq analysis pipeline utilizing four independent peak callers, which seamlessly processes raw sequencing files to final result. This approach enables (1) better gauging of peak confidence through detection by multiple algorithms, and (2) more thoroughly surveys the binding landscape by capturing peaks not detected by individual callers. Final analysis results are then integrated into a single output table, enabling users to explore their data by applying selectivity and sensitivity thresholds that best address their biological questions, without needing any additional reprocessing. ChIP-AP therefore presents investigators with a more comprehensive coverage of the binding landscape without requiring additional wet-lab observations.

Keywords: ChIP-seq; automated analysis pipeline; histone mark; integrated analysis pipeline; multiple peak callers; transcription factor binding.