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Engineering Approaches to Biomolecular Motors: From in vitro to in vivo Poster Abstracts
63
10-POS
Board 10
Microscopic Model for Force Generation in the ParA-ParB System
Eldon Emberly,
Lavisha Jindal
.
Simon Fraser University, Burnaby, BC, Canada.
Reconstitution of the ParA-ParB system in vitro has produced conclusive evidence that ParB
bound cargo can undergo directed motion when interacting with DNA bound ParA. Previously
we developed a continuum deterministic model for the in vitro system consisting of a ParB
decorated bead moving on a ParA decorated DNA substrate. The model involved only two
parameters that resulted from a mean field treatment of the net force acting on the bead due to
the ParA-ParB interaction. It predicted that for certain parameter values, constant speed motion
of the bead was possible with the possibility of an optimal speed. In order to determine the
validity of the continuum approximation made in the model, we have now performed stochastic
simulations of a microscopic model consisting of a ParB decorated polymer interacting with a
ParA substrate. We have explored the dependence of force generation in this model as a function
of the polymer size, the fraction of ParB, the density of ParA and the interaction energy.
Recently, it has been speculated that the elasticity of the DNA substrate may also facilitate force
generation. We also consider the effects of ParA substrate elasticity on the motion of the ParB
bound polymer. Our findings should help to bridge the gap on how forces are generated in the
ParA-ParB system from the length scales relevant in vitro all the way down to in vivo
.