Intranucleoid Diffusion Kinetics
Our previous work on the influence of genome organization on gene expression and regulation suggests that intracellular diffusion can be thought of as diffusion within and exchange between two distinct phases of material: the densely packed chromosomal nucleoid, and the less densely packed cytoplasm. We suspect that the diffusive kinetics within each of these intracellular phases is radically different and determined by the growth state and organization of the cell, and it is these differential diffusive kinetics that drive the inhomogeneous distribution of protein we have previously observed.
Figure 1: A cartoon illustrating our current model for understanding intracellular protein inhomogeneity as a consequence of bi-phasic intracellular diffusion.
We are currently extending our observations into live kinetic measurements in living E. coli to test this idea and to quantify the differences in diffusion of proteins and RNAs within the two distinct phases within the cell. More details coming soon!