Organismal Benefits of Transcription Speed Control at Gene Boundaries

We modulate RNAPII transcription speed by point mutations in the second largest subunit of Arabidopsis RNAPII, NRPB2. Nascent transcription profiling revealed that accelerated RNAPII complexes clear stalling sites at both gene ends, resulting in read-through transcription. Accelerated nascent RNAPII transcription increased the association with 5'SS intermediates and improved splicing efficiency, supporting tight connections between transcription speed and co-transcriptional pre-RNA processing. Plant native elongating transcripts sequencing (plaNET-Seq) was used to determine the genomic positions of transcriptionally engaged RNAPII in wild type and nrpb2-Y732F seedlings.