Overextended RNA:DNA hybrid as a negative regulator of RNA polymerase II processivity

J Mol Biol. 2000 Jun 2;299(2):325-35. doi: 10.1006/jmbi.2000.3755.

Abstract

An eight nucleotide RNA:DNA hybrid at the 3' end of the transcript is required for the stability of the elongation complex (EC) of RNA polymerase II. A non-template DNA strand is not needed for the stability of the EC, which contains this minimal hybrid. Here, we apply a recently developed method for promoter-independent assembly of functional EC of RNA polymerase II from synthetic RNA and DNA oligonucleotides to study the minimal composition of the nucleic acid array required for stability of the complex with RNA longer than eight nucleotides. We found that upon RNA extension beyond 14-16 nt in the course of transcription, non-template DNA becomes essential for maintaining a stable EC. Our data suggest that the overextended RNA:DNA hybrid formed in the absence the non-template DNA acts as a negative regulator of EC stability. The dissociation of the EC correlates with the backsliding of the polymerase along the overextended hybrid. The dual role of the hybrid provides a mechanism for the control of a correct nucleic acid architecture in the EC and of RNA polymerase II processivity.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Base Pair Mismatch / genetics
  • Base Pairing / genetics
  • Base Sequence
  • Binding Sites
  • Catalysis
  • DNA / chemistry
  • DNA / genetics
  • DNA / metabolism*
  • DNA, Single-Stranded / chemistry
  • DNA, Single-Stranded / genetics
  • DNA, Single-Stranded / metabolism
  • DNA-Binding Proteins / antagonists & inhibitors
  • DNA-Binding Proteins / metabolism
  • Enzyme Stability
  • Models, Genetic
  • Molecular Sequence Data
  • Nucleic Acid Heteroduplexes / chemistry*
  • Nucleic Acid Heteroduplexes / genetics
  • Nucleic Acid Heteroduplexes / metabolism*
  • Oligonucleotides / chemistry
  • Oligonucleotides / genetics
  • Oligonucleotides / metabolism
  • Potassium Permanganate / metabolism
  • Promoter Regions, Genetic / genetics
  • Protein Binding
  • RNA / biosynthesis
  • RNA / chemistry
  • RNA / genetics
  • RNA / metabolism*
  • RNA Polymerase II / antagonists & inhibitors*
  • RNA Polymerase II / metabolism*
  • RNA, Messenger / biosynthesis
  • RNA, Messenger / chemistry
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RNA-Binding Proteins / antagonists & inhibitors
  • RNA-Binding Proteins / metabolism
  • Templates, Genetic
  • Transcription, Genetic / genetics

Substances

  • DNA, Single-Stranded
  • DNA-Binding Proteins
  • Nucleic Acid Heteroduplexes
  • Oligonucleotides
  • RNA, Messenger
  • RNA-Binding Proteins
  • Potassium Permanganate
  • RNA
  • DNA
  • RNA Polymerase II