Flexible analysis of TSS mapping data and detection of TSS shifts with TSRexploreR

Abstract

Heterogeneity in transcription initiation has important consequences for transcript stability and translation, and shifts in transcription start site (TSS) usage are prevalent in various disease and developmental contexts. Accordingly, numerous methods for global TSS profiling have been developed, including our recently published Survey of TRanscription Initiation at Promoter Elements with high-throughput sequencing (STRIPE-seq), a method to profile transcription start sites (TSSs) on a genome-wide scale with minimal cost and time. In parallel to our development of STRIPE-seq, we built TSRexploreR, an R package for end-to-end analysis of TSS mapping data. TSRexploreR provides functions for TSS and TSR detection, normalization, correlation, visualization, and differential TSS/TSR analysis. TSRexploreR is highly interoperable, accepting the data structures of TSS and TSR sets generated by several existing tools for processing and alignment of TSS mapping data, such as CAGEr for Cap Analysis of Gene Expression (CAGE) data. Lastly, TSRexploreR implements a novel approach for the detection of shifts in TSS distribution.