Gene length delays mRNA production. (A) Transcription across the CACNA1C gene body. Ridges display normalized RNA-seq coverage over 1-kb intervals tiled across CACNA1C introns. Color intensity indicates the scaled expression of each 1-kb interval across the time course. A right-facing arrow at the 5′ end of the gene schematic (top) indicates the direction of transcription. (B–E) mRNA and pre-mRNA expression dynamics for four genes of varying length. Pre-mRNA expression is shown for the first and last 10 kb of each gene's introns, indicated above each gene schematic by blue and red horizontal bars, respectively. The approximate delay between transcription of the first and last 10 kb of pre-mRNA is indicated by a left-right arrow between the two expression profile peaks. Expression profiles are overlaid with impulse model fits (lines) and scaled to values between zero and one to facilitate visual comparison.
