C25, an essential RNA polymerase III subunit related to the RNA polymerase II subunit RPB7.

AUTOR(ES)

Sadhale, P P

RESUMO

We identified a partially sequenced Saccharomyces cerevisiae gene which encodes a protein related to the S. cerevisiae RNA polymerase II subunit, RPB7. Several lines of evidence suggest that this related gene, YKL1, encodes the RNA polymerase III subunit C25. C25, like RPB7, is present in submolar ratios, easily dissociates from the enzyme, is essential for cell growth and viability, but is not required in certain transcription assays in vitro. YKL1 has ABF-1 and PAC upstream sequences often present in RNA polymerase subunit genes. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis mobility of the YKL1 gene product is equivalent to that of the RNA polymerase III subunit C25. Finally, a C25 conditional mutant grown at the nonpermissive temperature synthesizes tRNA at reduced rates relative to 5.8S rRNA, a hallmark of all characterized RNA polymerase III mutants.

Documentos Relacionados

• RNA polymerase II subunit RPB3 is an essential component of the mRNA transcription apparatus.
• Rpb7 subunit of RNA polymerase II interacts with an RNA-binding protein involved in processing of transcripts
• An Rpb4/Rpb7-Like Complex in Yeast RNA Polymerase III Contains the Orthologue of Mammalian CGRP-RCP
• Loss of the Rpb4/Rpb7 Subcomplex in a Mutant Form of the Rpb6 Subunit Shared by RNA Polymerases I, II, and III
• Analysis of the Interaction of the Novel RNA Polymerase II (pol II) Subunit hsRPB4 with Its Partner hsRPB7 and with pol II