Diffusion of proteins in chloroplast membranes

The lateral diffusion of Hcf106, a core subunit of the ΔpH-dependent translocon in higher plants, and chlorophyll-containing complexes is thoroughly investigated by Fluorescent Recovery After Photobleaching (FRAP) and Fluorescent Loss in Photobleaching (FLIP). Simple models of a thylakoid network are derived directly from confocal fluorescence microscopy images by Monte Carlo optimisation. These networks are used as the domain for diffusion simulations using the Particle Strength Exchange method, allowing determination of diffusion coefficients for the thylakoid protein Hcf106 and for chlorophyll-containing complexes. Extending the mobility studies to the chloroplast outer membrane, diffusion coefficients are estimated for Toc159, a component of the chloroplast outer membrane translocon TOC