Vesicular tubular transporters are in transit, moving along microtubules between the **endoplasmic reticulum (ER)** and the **Golgi apparatus**.
The endoplasmic reticulum is an interconnected network of tubules and sacs involved in protein synthesis, lipid metabolism, and calcium storage. The Golgi apparatus is a stack of flattened membranes that processes, modifies, and sorts proteins and lipids synthesized in the ER before they are transported to their final destinations within the cell or secreted outside of the cell.
Vesicular tubular transporters facilitate the transport of molecules, such as proteins and lipids, between these two structures. They use the microtubules, which are part of the cytoskeleton, as tracks or "roads" for their movement. The microtubules provide the structural support and guidance necessary for the vesicles and tubules to reach their intended destinations.