A motor that makes its own track: helicase unwinding of DNA.
We study the unwinding of DNA by helicase proteins as a representative system in which a motor protein interacts with a mobile obstacle. In our discrete model, the interaction between the helicase and the DNA fork is characterized by an interaction potential. For the case of a hard-wall potential, the helicase opens the DNA by rectifying thermal fluctuations which spontaneously open base pairs. A potential with nonzero range describes the destabilization of the double strand by the enzymatic action of the helicase. We derive solutions for the opening speed as a function of the potential shape and relate our results to experiments on helicase motion.
Betterton
M D
MD
Insitut Curie, Physico-chimie Curie, UMR 168, 26 rue d'Ulm, 75248 Paris Cedex 05, France. mdb@colorado.edu
Jülicher
Frank
F
D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D004265:DNA Helicases / Q000737:chemistry / Q000378:metabolism*; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000378:metabolism; D008956:Models, Chemical; D013816:Thermodynamics
D004277:DNA, Single-Stranded; D004247:DNA; D004265:DNA Helicases