Fig. 2: Structural alterations in the CG, TG and TT complexes.
From: Structural basis of error-prone DNA synthesis by DNA polymerase θ
a Finger domain movements in the CG complex (blue) compared to human Pol θ crystal structure (7ZUS, orange) and Pol I (3KTQ, yellow). The Mg2+ ions, incoming nucleotides, and critical residues for catalysis are shown as sphere and sticks, respectively. b Comparison of the finger domain conformation in the CG, TG (magenta) and TT (green) complexes. c Comparison of the finger domain conformation in the TT complex with that observed in Pol I structures. The finger domain in the TT complex remains closed, similar to that in Pol I bound with a cognate nascent base pair (3KTQ, yellow). However, it differs from the ajar conformation of Pol I with a mismatched base pair in its active site (3HP6, purple). d Conformation of the nascent base pairs in the three structures. Hydrogen bonds between the templating base and the incoming nucleotide are indicated by dashed lines, and the electron density map is displayed as meshes. Atoms involved in hydrogen bonding are labeled.
