NTP-entry routes in multi-subunit RNA polymerases.
The recent elucidation of crystal structures for multi-subunit RNA polymerases immediately revealed a mystery: how do nucleotide triphosphate (NTP) substrates reach an active site that is buried deep within the enzyme? The prevailing view is that NTPs enter through an approximately 20A-long secondary channel between the active site and the enzyme surface. Recently, an alternative view has been advocated; namely, NTPs enter the active site pre-bound to the DNA template from the downstream DNA portion of the main channel of the enzyme.
Landick
Robert
R
Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA. landick@bact.wisc.edu
D001693:Biological Transport, Active; D020134:Catalytic Domain; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry* / Q000378:metabolism*; D008954:Models, Biological; D008958:Models, Molecular; D009711:Nucleotides / Q000378:metabolism*; D011487:Protein Conformation; D021122:Protein Subunits
D009711:Nucleotides; D021122:Protein Subunits; D012321:DNA-Directed RNA Polymerases