Golgi Apparatus - Cisternal Maturation Model

The cisternal maturation model posits that cisternae are transient structures; they disassemble and new ones are constructed.
Vesicles originating from the ER fuse together, not to an existing CGN, but to create a new CGN.
Once the new CGN is established, the previous CGN transitions to become the MGN (medial-Golgi network).
Subsequently, the former MGN transforms into the TGN (trans-Golgi network).
The TGN disassembles as vesicles bud off from it to transport their contents to various destinations.
The TGN essentially ceases to exist after vesicle budding.
The process involves the formation of a new CGN from vesicles, after which the existing CGN, MGN, and TGN sequentially shift roles as the TGN breaks down into vesicles.
Retrograde transport still occurs via vesicles budding off and fusing to transport materials back to previous compartments.
Movement from CGN to TGN is facilitated by the structural transformation of entire cisternae.

Retrograde transport, which involves vesicles budding off one compartment (such as the old TGN) and fusing with another, allowing for the transfer of necessary components between Golgi structures.

Evidence suggests that both the vesicular transport model and the cisternal maturation model are functional within cells.
The specific model utilized depends on the organism and the specific function of the cell.
Both models have been observed in different cell types.