Identification of a 3'-->5' exonuclease activity associated with human RNA polymerase II.
AUTOR(ES)
Wang, D
RESUMO
Human RNA polymerase II is shown to be associated with a 3'-->5' exonuclease activity that removes nucleoside 5'-monophosphates from the 3' end of the transcripts in isolated ternary complexes. This activity is stimulated by SII, a protein that acts as a transcription elongation factor in vitro. In addition, we show that another transcription factor, TFIIF, stimulates a competing pyrophosphorolysis reaction. These findings raise interesting questions about the roles of these activities in vivo, including the possibility that this RNA polymerase may proofread the nascent transcript.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=45766Documentos Relacionados
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