[Electron-tomographic analysis of the Golgi complex structure in cultured cells].

Study of the Golgi complex (GC) in cultured NRK cells using improved method of sample preparation for electron tomography (ET) enabled to detect more fine details of GC structure. With the application of quantitative ET, no numerous vesicles were detected around GC, while most of stacks constantly contained intercisternal connections. It was demonstrated that vesicular-tubular clusters, which serve as the exit sites from endoplasmic reticulum, were composed of two domains: varicose tubules with sparse COPII-coated vesicles and a network of smooth tubules. The data obtained argue against the models of transport, which consider the vesicles as the main or necessary membranous carriers. On the contrary, continuous tubular connections seem to play an important role in traffic joining secretory pathway regions.