BREAKING NONLINEARITY WITH PARTIAL BLEACHING SIMPLIFIES THE ANALYSIS OF BIOMOLECULE TRANSPORT OBSERVATIONS IN INTACT CELLS.

PEREZ IPIÑA, EMILIANO; PONCE DAWSON, SILVINA

Montevideo

Conferencia; Montevideo Dynamical Systems Conference 2012; 2012

Diffusion is one of the main transport processes that occur inside cells determining the spatial and time distribution of relevant action molecules. In most cases these molecules not only diffuse but also interact with others as they get transported. Under certain conditions the net resulting transport is still approx- imately diffusive but with an effective (concentration-dependent) rather than free diffusion coefficient. By fluorescently-labeling the biomolecules it is possible to use optical techniques to infer the rate at which this net transport occurs in intact cells. Interpreting the experimental results is complicated since effective coefficients are not unique. In this paper we discuss how some coefficients are derived from intrinsically linear problems while others are not. We then show how, when probing transport in intact cells with op- tical techniques, we can obtain one or another type of coefficient by partially bleaching the population of tagged biomolecules. This provides a useful tool to extract more quantitative information from a living system with minimum disruption.