Transcriptional activators enhance polyadenylation of mRNA precursors

Mol Cell. 2011 Feb 18;41(4):409-18. doi: 10.1016/j.molcel.2011.01.022.

Abstract

Polyadenylation of mRNA precursors is frequently coupled to transcription by RNA polymerase II. Although this coupling is known to involve interactions with the C-terminal domain of the RNA polymerase II largest subunit, the possible role of other factors is not known. Here we show that a prototypical transcriptional activator, GAL4-VP16, stimulates transcription-coupled polyadenylation in vitro. In the absence of GAL4-VP16, specifically initiated transcripts accumulated but little polyadenylation was observed, while in its presence polyadenylation was strongly enhanced. We further show that this stimulation requires the transcription elongation-associated PAF complex (PAF1c), as PAF1c depletion blocked GAL4-VP16-stimulated polyadenylation. Furthermore, knockdown of PAF subunits by siRNA resulted in decreased 3' cleavage, and nuclear export, of mRNA in vivo. Finally, we show that GAL4-VP16 interacts directly with PAF1c and recruits it to DNA templates. Our results indicate that a transcription activator can stimulate transcription-coupled 3' processing and does so via interaction with PAF1c.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Cells, Cultured
  • Humans
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Polyadenylation*
  • RNA Polymerase II / genetics
  • RNA Polymerase II / metabolism
  • RNA Precursors / metabolism*
  • RNA, Messenger / metabolism*
  • RNA, Small Interfering / metabolism
  • Trans-Activators / genetics
  • Trans-Activators / metabolism*
  • Transcription, Genetic
  • Transfection

Substances

  • Gal-VP16
  • Nuclear Proteins
  • RNA Precursors
  • RNA, Messenger
  • RNA, Small Interfering
  • Trans-Activators
  • RNA Polymerase II
  • RNA polymerase II largest subunit