TY - JOUR
T1 - Elastic coupling between RNA degradation and unwinding by an exoribonuclease
AU - Lee, Gwangrog
AU - Bratkowski, Matthew A.
AU - Ding, Fang
AU - Ke, Ailong
AU - Ha, Taekjip
PY - 2012/6/29
Y1 - 2012/6/29
N2 - Rrp44 (Dis3) is a key catalytic subunit of the yeast exosome complex and can processively digest structured RNA one nucleotide at a time in the 3′ to 5′ direction. Its motor function is powered by the energy released from the hydrolytic nuclease reaction instead of adenosine triphosphate hydrolysis as in conventional helicases. Single-molecule fluorescence analysis revealed that instead of unwinding RNA in single base pair steps, Rrp44 accumulates the energy released by multiple single nucleotide step hydrolysis reactions until about four base pairs are unwound in a burst. Kinetic analyses showed that RNA unwinding, not cleavage or strand release, determines the overall RNA degradation rate and that the unwinding step size is determined by the nonlinear elasticity of the Rrp44/RNA complex, but not by duplex stability.
AB - Rrp44 (Dis3) is a key catalytic subunit of the yeast exosome complex and can processively digest structured RNA one nucleotide at a time in the 3′ to 5′ direction. Its motor function is powered by the energy released from the hydrolytic nuclease reaction instead of adenosine triphosphate hydrolysis as in conventional helicases. Single-molecule fluorescence analysis revealed that instead of unwinding RNA in single base pair steps, Rrp44 accumulates the energy released by multiple single nucleotide step hydrolysis reactions until about four base pairs are unwound in a burst. Kinetic analyses showed that RNA unwinding, not cleavage or strand release, determines the overall RNA degradation rate and that the unwinding step size is determined by the nonlinear elasticity of the Rrp44/RNA complex, but not by duplex stability.
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U2 - 10.1126/science.1216848
DO - 10.1126/science.1216848
M3 - Article
C2 - 22745434
AN - SCOPUS:84862991581
VL - 336
SP - 1726
EP - 1729
JO - Science
JF - Science
SN - 0036-8075
IS - 6089
ER -