Direct RNA Sequencing
Genome-wide Profiling of Polyadenylation Sites by Direct RNA Sequencing
The emerging discoveries on the link between polyadenylation and disease states underline the need to fully characterize genome-wide polyadenylation states. We here employed the improvements in the Direct RNA Sequencing technology and mapped global polyadenylation events in human and yeast. This direct approach provides a quantitative view of genome-wide polyadenylation states in a strand-specific manner and requires only attomole RNA quantities. Polyadenylation profiles revealed an abundance of unannotated polyadenylation sites, alternative polyadenylation patterns, and regulatory element-associated polyA RNAs. We observed differences in sequence composition surrounding canonical and non-canonical human polyadenylation sites, suggesting novel non-coding RNA-specific polyadenylation mechanisms in humans. Furthermore, we observed the correlation level between sense and antisense transcripts to depend on gene expression levels, supporting the view that overlapping transcription from opposite strands may play a regulatory role. Our data provide a comprehensive view of the polyadenylation state and overlapping transcription.
Transcriptome profiling with Direct RNA Sequencing.