This is a tour of a physical model of the T7 virus RNA polymerase (PDB ID 1msw).
Above is a photograph of the two parts of the model. To assemble it, you bring the two flat sides together (the view is a "butterflied" version of the structure). On the left is the N-terminal part (roughly) with the nucleic acid forming a transcription bubble. On the right is the C-terminal part (roughly), in the shape of the right hand, with the active site at the palm. For an annotated image, see below.
You can track the video in the interactive scene by clicking the timestamp buttons. (initial scene)
The video starts with a view of the N-terminal part of the protein. You can see the exiting template DNA (blue) on the right. As the model rotates, the active site comes into view. In red, you can see the most recently added nucleotide (about 10 seconds in). The active site is formed by the C-terminal part of the protein, which is shaped like a right hand. Access to the active site (the "palm" of the hand) is in between the "thumb" (in front about 7 sec in) and "the fingers" (in front about 14 sec in). At 22 s in, you have view on the helical axis of the upstream DNA. At about 30 s in, you can see the RNA exit channel. At 36 s, we are back to the start, and you can press "rewatch" on the YouTube window to take another turn.
Also, use the widgets below to change representations.
Protein shown as
References
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