A movie of the RNA polymerase nucleotide addition cycle
Curr. Opin. Struct. Biol., 2009, 19(3), 294-299, doi:10.1016/j.sbi.2009.04.005 published on 27.05.2009
Curr. Opin. Struct. Biol., online article
During gene transcription, RNA polymerase (Pol) passes through repetitive cycles of adding a nucleotide to the growing mRNA chain. Here we obtained a movie of the nucleotide addition cycle by combining structural information on different functional states of the Pol II elongation complex (EC). The movie illustrates the two-step loading of the nucleoside triphosphate (NTP) substrate, closure of the active site for catalytic nucleotide incorporation, and the presumed two-step translocation of DNA and RNA, which is accompanied by coordinated conformational changes in the polymerase bridge helix and trigger loop. The movie facilitates teaching and a mechanistic analysis of transcription and can be downloaded from http://www.lmb.uni-muenchen.de/cramer/pr-materials.