On page , Rossanese et al. suggest that the Golgi is an outgrowth of the endoplasmic reticulum (ER), and that this property can explain the divergent organization of the Golgi in two yeast species.
The context for the paper involves two competing theories of Golgi organization. Both implicate transport vesicles: in the stable compartments model, the vesicles carry out anterograde transport of secretory cargo between Golgi cisternae of constant composition; in the cisternal maturation model, the vesicles recycle Golgi components to ever earlier cisternae as the cisternae mature and move through the stack. The latter model involves bulk transport of components by maturation of the Golgi stacks.
If the cisternae are progressing and maturing, new cisternae must be created. Rossanese et al. propose that the cisternae are created near transitional ER (tER) sites, where vesicles bud from the ER. In Saccharomyces cerevisiae, a species with a dispersed Golgi,...
