The RNA Polymerase II Elongation Complex- Factor-Dependent Transcription Elongation Involves Nascent RNA Cleavage

• Authors: Daniel Reines, Emory University; Pejman Ghanouni, Emory University; Qing-qin Li, Emory University; John Mote, Jr., Emory University
• Journal Title: Journal of Biological Chemistry
• Volume: Volume 267, Number 22
• Publisher: American Society for Biochemistry and Molecular Biology | 1992-08-05, Pages 15516-15522
• Type of Work: Article | Final Publisher PDF
• Subjects: Biology, Molecular; Chemistry, Biochemistry
• Keywords: Science & Technology; Life Sciences & Biomedicine; Biochemistry & Molecular Biology; FACTOR-S-II; FACTOR-SII; PREMATURE TERMINATION; TERNARY COMPLEXES; DNA-SEQUENCE; GENE; PURIFICATION; INVITRO; INVIVO; TFIIS

Abstract

Regulation of transcription elongation is an important mechanism in controlling eukaryotic gene expression. SII is an RNA polymerase II-binding protein that stimulates transcription elongation and also activates nascent transcript cleavage by RNA polymerase II in elongation complexes in vitro (Reines, D. (1992) J. Biol. Chem. 267, 3795-3800). Here we show that SII-dependent in vitro transcription through an arrest site in a human gene is preceded by nascent transcript cleavage. RNA cleavage appeared to be an obligatory step in the SII activation process. Recombinant SII activated cleavage while a truncated derivative lacking polymerase binding activity did not. Cleavage was not restricted to an elongation complex arrested at this particular site, showing that nascent RNA hydrolysis is a general property of RNA polymerase II elongation complexes. These data support a model whereby SII stimulates elongation via a ribonuclease activity of the elongation complex.