Active phase separation on cell membranes

The spatial organization of cellular membranes is crucial for intracellular trafficking processes, where membrane-bound Rab GTPases play a central role. This study explores the formation and dynamics of Rab protein domains, focusing specifically on Rab5 and Rab11, and examines their structural organization and functional roles in endosomal trafficking. Rab proteins act as molecular switches that regulate distinct stages of the endocytic pathway by recruiting various effectors, thereby orchestrating vesicle transport. . Building on previous studies of Rab5/Rab7 domains, we develop a computational model to simulate the formation of Rab5/Rab11 domains. Our simulations demonstrate how, starting from a homogeneous distribution, interactions and reactions among Rab5 and Rab11 proteins lead to the emergence of distinct domains, enhancing our understanding of membrane compartmentalization in cellular trafficking. Using high-resolution imaging and advanced quantitative analyses, we characterize the clustering patterns of Rab domains and their association with specific membrane compartments. A SODA analysis is used, this method does not depend on the PSF characteristics because it focuses on analyzing the spatial relationships between molecular positions and not on the exact appearance or intensity distribution of those points in an image. We analyzed two sets of cellular images treated with Nocodazole and Vps34-IN1 to investigate the impact of these compounds on Rab domain formation.