Single-molecule tracking of mRNA exiting from RNA polymerase II.
Single-pair fluorescence resonance energy transfer was used to track RNA exiting from RNA polymerase II (Pol II) in elongation complexes. Measuring the distance between the RNA 5' end and three known locations within the elongation complex allows us determine its position by means of triangulation. RNA leaves the polymerase active center cleft via the previously proposed exit tunnel and then disengages from the enzyme surface. When the RNA reaches lengths of 26 and 29 nt, its 5' end associates with Pol II at the base of the dock domain. Because the initiation factor TFIIB binds to the dock domain and exit tunnel, exiting RNA may prevent TFIIB reassociation during elongation. RNA further extends toward the linker connecting to the polymerase C-terminal repeat domain (CTD), which binds the 5'-capping enzyme and other RNA processing factors.
Andrecka
Joanna
J
Munich Center for Integrated Protein Science (CiPS) and Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität München, 81377 Munich, Germany.
Lewis
Robert
R
Brückner
Florian
F
Lehmann
Elisabeth
E
Cramer
Patrick
P
Michaelis
Jens
J
D003545:Cysteine / Q000737:chemistry; D004257:DNA Polymerase II / Q000737:chemistry; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D005656:Fungal Proteins / Q000737:chemistry*; D007834:Lasers; D008958:Models, Molecular; D015233:Models, Statistical; D008968:Molecular Conformation; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D009841:Oligonucleotides / Q000737:chemistry; D017434:Protein Structure, Tertiary; D012313:RNA / Q000737:chemistry; D012319:RNA Polymerase II / Q000737:chemistry*; D012333:RNA, Messenger / Q000737:chemistry*; D035581:Transcription Factor TFIIB / Q000737:chemistry
D005656:Fungal Proteins; D009841:Oligonucleotides; D012333:RNA, Messenger; D035581:Transcription Factor TFIIB; D012313:RNA; D012319:RNA Polymerase II; D004257:DNA Polymerase II; D003545:Cysteine