Distinct regions of RPB11 are required for heterodimerization with RPB3 in human and yeast RNA polymerase II

Nucleic Acids Res. 2005 Jun 24;33(11):3582-90. doi: 10.1093/nar/gki672. Print 2005.

Abstract

In Saccharomyces cerevisiae, RNA polymerase II assembly is probably initiated by the formation of the RPB3-RPB11 heterodimer. RPB3 is encoded by a single copy gene in the yeast, mouse and human genomes. The RPB11 gene is also unique in yeast and mouse, but in humans a gene family has been identified that potentially encodes several RPB11 proteins differing mainly in their C-terminal regions. We compared the abilities of both yeast and human proteins to heterodimerize. We show that the yeast RPB3/RPB11 heterodimer critically depends on the presence of the C-terminal region of RPB11. In contrast, the human heterodimer tolerates significant changes in RPB11 C-terminus, allowing two human RPB11 variants to heterodimerize with the same efficiency with RPB3. In keeping with this observation, the interactions between the conserved N-terminal 'alpha-motifs' is much more important for heterodimerization of the human subunits than for those in yeast. These data indicate that the heterodimerization interfaces have been modified during the course of evolution to allow a recent diversification of the human RPB11 subunits that remains compatible with heterodimerization with RPB3.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Cell Proliferation
  • Conserved Sequence
  • Dimerization
  • Humans
  • Molecular Sequence Data
  • Mutation
  • Protein Structure, Tertiary
  • Protein Subunits / chemistry
  • Protein Subunits / metabolism
  • RNA Polymerase II / chemistry*
  • RNA Polymerase II / genetics
  • RNA Polymerase II / metabolism
  • Saccharomyces cerevisiae Proteins / chemistry*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism
  • Two-Hybrid System Techniques

Substances

  • Protein Subunits
  • Saccharomyces cerevisiae Proteins
  • POLR2C protein, human
  • POLR2J protein, human
  • RNA Polymerase II
  • RPB11 protein, S cerevisiae
  • RPB3 protein, S cerevisiae