Movie S4.

Conformational intermediates identified through clustering analysis of the molecular dynamics’ trajectories. Electrostatic interactions between Orc1-6, Mcm2-7 and dsDNA facilitate the passage of the dsDNA through the loading gate. Residue-level contacts are shown as spheres. Near the end of the transition, the Mcm4-WHD passes through the opening created by the Orc1-6 and Mcm2-7. State S9 captures the Mcm4-WHD wedged between the Orc1-6 and Mcm2-7.