Fidelity of RNA polymerase II transcription controlled by elongation factor TFIIS

AUTOR(ES)

Jeon, ChoonJu

FONTE

The National Academy of Sciences of the USA

RESUMO

Fidelity of DNA and protein synthesis is regulated by a proofreading mechanism but function of a similar mechanism during RNA synthesis has not been demonstrated. Analysis of transcriptional fidelity and its control has been hampered by the necessity to employ complex DNA templates requiring either a promoter and initiation factors or 3′-extended templates. To circumvent this difficulty, we have created an RNA–DNA dumbbell template that can be recognized as a template-primer and extended by RNA polymerase II. By employing this system, we demonstrate that RNA polymerase II can misincorporate a nucleotide and carry out template-dependent elongation at the mispaired end. The transcripts containing misincorporated residues can be cleaved by the very slow 3′ → 5′ ribonuclease activity of the RNA polymerase II, but enhancement of this activity by the elongation factor TFIIS generates RNA with a high degree of fidelity. This enhanced preferential cleavage of misincorporated transcripts suggests an important role for TFIIS in maintaining transcriptional fidelity.

Documentos Relacionados

• Genetic interaction between transcription elongation factor TFIIS and RNA polymerase II.
• The transcription factor TFIIS zinc ribbon dipeptide Asp-Glu is critical for stimulation of elongation and RNA cleavage by RNA polymerase II.
• The Rpb6 Subunit of Fission Yeast RNA Polymerase II Is a Contact Target of the Transcription Elongation Factor TFIIS
• In vitro characterization of mutant yeast RNA polymerase II with reduced binding for elongation factor TFIIS.
• Synthesis of reinitiated transcripts by mammalian RNA polymerase II is controlled by elongation factor SII.