Figure 7: Model for DNA conformational rearrangements during telomerase catalytic cycle.
From: Coordinated DNA dynamics during the human telomerase catalytic cycle
(i) Telomerase initially binds a telomere DNA substrate through RNA:DNA hybrid interactions with the template and additional 5′-DNA contacts. Rapid synthesis of a complete telomere DNA repeat extends the RNA:DNA hybrid to the template boundary, at which point a dynamic equilibrium of DNA primer states exists (ii), favoring the formation of a realigned RNA:DNA hybrid. (iii) In a second, rate-limiting, step of RAP, the realigned RNA:DNA hybrid is repositioned in the telomerase active site and the 5′-end of the DNA primer is extruded from the enzyme complex.
