Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
J Biol Chem. 1995 May 12;270(19):11398-405.

Lethal mutations in a yeast U6 RNA gene B block promoter element identify essential contacts with transcription factor-IIIC.

Author information

  • 1Department of Biomolecular Chemistry, University of Wisconsin Medical School, Madison 53706-1532, USA.

Abstract

The B block promoter element is the primary binding site for the RNA polymerase III transcription initiation factor TFIIIC. It is always located within the transcript coding region, except in the Saccharomyces cerevisiae U6 RNA gene (SNR6), in which the B block lies 120 base pairs downstream of the terminator. We have exploited the unique location of the SNR6 B block to examine the sequence specificity of its interaction with TFIIIC. The in vitro and in vivo effects of all possible single base pair substitutions in the 9-base pair core of the B block were determined. Five mutant alleles are recessive lethal when present at a low copy number; these alleles identify crucial contacts between TFIIIC and the B block promoter element. Transcript analysis reveals that lethal B block substitutions reduce U6 RNA synthesis at least 10-fold in vivo and 20-fold in vitro. One viable B block mutant strain has one-third the wild type amount of U6 RNA and exhibits reduced levels of the U4-U6 RNA complex required for spliceosome assembly. The locations of lethal single and double point mutations leads us to propose that two domains of TFIIIC contact overlapping sites on the B block element.

PMID:
7744776
[PubMed - indexed for MEDLINE]
Free full text

LinkOut - more resources

Full Text Sources

Other Literature Sources

Molecular Biology Databases

PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk