The C-terminal repeat domain of RNA polymerase II largest subunit is essential in vivo but is not required for accurate transcription initiation in vitro.


Journal Article

DNA sequence analysis of RpII215, the gene that encodes the Mr215,000 subunit of RNA polymerase II (EC in Drosophila melanogaster, reveals that the 3'-terminal exon includes a region encoding a C-terminal domain composed of 42 repeats of a seven-residue amino acid consensus sequence, Tyr-Ser-Pro-Thr-Ser-Pro-Ser. A hemi- and homozygous lethal P-element insertion into the coding sequence of this domain causes premature translation termination and therefore truncation of the protein, leaving only 20 heptamer repeats. While loss of approximately 50% of the repeat structure in this mutant is a lethal event in vivo, enzyme containing the truncated subunit remains capable of accurate initiation at promoters in vitro. Moreover, treatment of purified intact RNA polymerase II with protease, to remove the entire repeat domain, does not eliminate the enzyme's ability to initiate accurately in vitro. Possible in vivo functions for this unusual protein domain are considered in light of these results.

Full Text

Duke Authors

Cited Authors

  • Zehring, WA; Lee, JM; Weeks, JR; Jokerst, RS; Greenleaf, AL

Published Date

  • June 1988

Published In

Volume / Issue

  • 85 / 11

Start / End Page

  • 3698 - 3702

PubMed ID

  • 3131761

Pubmed Central ID

  • 3131761

International Standard Serial Number (ISSN)

  • 0027-8424

Digital Object Identifier (DOI)

  • 10.1073/pnas.85.11.3698


  • eng

Conference Location

  • United States