Transport through the Golgi Apparatus by Rapid Partitioning within a Two-Phase Membrane System

摘要: The prevailing view of intra-Golgi transport is cisternal progression, which has a key prediction--that newly arrived cargo exhibits lag or transit time before exiting the Golgi. Instead, we find that molecules exit at an exponential rate proportional to their total Golgi abundance with no lag. Incoming rapidly mix those already in system and from partitioned domains privileged for export based on its entry into system. Given these results, constructed new model involves rapid partitioning enzymes transmembrane between two lipid phases combined relatively exchange among cisternae. Simulation experimental testing this reproduced all characteristics apparatus, including polarized protein gradients, kinetics, waves.