試題詳解

9. Crystal structures of the transcription elongation complex involving RNA polymerase II reveal a clamp, three loops of the clamp (called the lid, rudder and zipper), and a bridge helix.
(A) The function of the lid is to initiate dissociation of the RNA-DNA hybrid.
(B) The zipper appears to play a role to maintain the dissociation of the template DNA.
(C) The bridge helix appears to play a role to maintain the dissociation of the RNA-DNA hybrid.
(D) The rudder is speculated to play a role in translocation during transcription.
(E) Alpha-amanitin is bound to a site near the bridge helix appears to enhance translocation during transcription.