Extended Data Fig. 2: Cryo-EM density in the catalytic site and different J1/2 conformations, related to Fig. 1.
From: Cryo-EM reveals dynamics of Tetrahymena group I intron self-splicing
(a) Superposition of J1/2 in different states reveals conformational changes. (b) Superposition of all conformations with previous apo L-21 ScaI ribozyme reveals almost identical global architecture and apparent conformational changes of P1/P1′ helix. IGS of apo L-21 ScaI ribozyme, P1 helix of relaxed pre-Tet-S1 and P1′ helix of pre-Tet-C are in the same relaxed position. (c) nucleotides of J1/2 are stacked in pre-Tet-C at 4.0σ threshold. (d-e) Cryo-EM density connectivity of Tet-S2a (d) and Tet-S2b (e) at 3.0σ and 4.0σ threshold reveals connection of ωG with u(+1) in 3′-exon and cleaved 5′-exon, indicating that these conformations are prior to the second step of splicing.
