The C-terminal domain of the largest subunit of RNA polymerase II interacts with a novel set of serine/arginine-rich proteins

Proc Natl Acad Sci U S A. 1996 Jul 9;93(14):6975-80. doi: 10.1073/pnas.93.14.6975.


Although transcription and pre-mRNA processing are colocalized in eukaryotic nuclei, molecules linking these processes have not previously been described. We have identified four novel rat proteins by their ability to interact with the repetitive C-terminal domain (CTD) of RNA polymerase II in a yeast two-hybrid assay. A yeast homolog of one of the rat proteins has also been shown to interact with the CTD. These CTD-binding proteins are all similar to the SR (serine/arginine-rich) family of proteins that have been shown to be involved in constitutive and regulated splicing. In addition to alternating Ser-Arg domains, these proteins each contain discrete N-terminal or C-terminal CTD-binding domains. We have identified SR-related proteins in a complex that can be immunoprecipitated from nuclear extracts with antibodies directed against RNA polymerase II. In addition, in vitro splicing is inhibited either by an antibody directed against the CTD or by wild-type but not mutant CTD peptides. Thus, these results suggest that the CTD and a set of CTD-binding proteins may act to physically and functionally link transcription and pre-mRNA processing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Arginine*
  • Binding Sites
  • Carrier Proteins / biosynthesis
  • Carrier Proteins / chemistry*
  • Carrier Proteins / metabolism*
  • Consensus Sequence
  • Macromolecular Substances
  • Mice
  • Molecular Sequence Data
  • RNA Polymerase II / chemistry*
  • RNA Polymerase II / metabolism*
  • RNA-Binding Proteins / chemistry
  • Rats
  • Recombinant Fusion Proteins / metabolism
  • Saccharomyces cerevisiae / metabolism
  • Sequence Homology, Amino Acid
  • Serine*


  • Carrier Proteins
  • Macromolecular Substances
  • RNA-Binding Proteins
  • Recombinant Fusion Proteins
  • Serine
  • Arginine
  • RNA Polymerase II

Associated data

  • GENBANK/U49055
  • GENBANK/U49056
  • GENBANK/U49057
  • GENBANK/U49058