Open AccessA novel RNA polymerase I-dependent RNase activity that shortens nascent transcripts from the 3′ end
Author(s) -
Herbert Tschochner
Publication year - 1996
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.93.23.12914
Subject(s) - termination factor , rna polymerase ii , microbiology and biotechnology , rnase h , rna , biology , transcription (linguistics) , rnase p , transcription factor ii e , polymerase , rna polymerase i , dna , rna polymerase ii holoenzyme , rna dependent rna polymerase , genetics , gene , gene expression , promoter , linguistics , philosophy
A novel RNase activity was identified in a yeast RNA polymerase I (pol I)in vitro transcription system. Transcript cleavage occurred at the 3′ end and was dependent on the presence of ternary pol I/DNA/RNA complexes and an additional protein factor not identical to transcription factor IIS (TFIIS). Transcript cleavage was observed both on arrested complexes at the linearized ends of the transcribed DNA and on intrinsic blocks of the DNA template. Shortened transcripts that remained associated within the ternary complexes were capable of resuming RNA chain elongation. Possible functions of the nuclease for transcript elongation or termination are discussed.