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Figure 5.
Schematic description of the sequential coordination of
hydrolysis. A, top panel shows a schematic representation of the
conserved motifs in the context of one P4 subunit together with
a bound ATP (yellow). B, initial state before hydrolysis. Only
three consecutive subunits of the unraveled hexamer are shown
for clarity (as perceived from the central channel, i.e. from
the bound RNA “perspective”). C, hydrolysis and P[i] release
from subunit i -1 allows the downward movement of helix α6 and
insertion of the arginine finger Arg-279 into subunit i active
site (ADP-P^* designates the transition state). The L2 loop
drags down the bound RNA (cyan). D, next round of sequential
hydrolysis. The stretched RNA (a stress loop, magenta) links L2
loops on i and i -1. RNA is brought to the vicinity and binds to
L2 at subunit i + 1.
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