What is the Difference Between Cisternae and Tubules?

Cisternae and tubules are distinct regions within the endoplasmic reticulum (ER) that have different functions and structures:

• Cisternae are found in the rough endoplasmic reticulum (RER) and are involved in protein packaging and modification. They are comprised of extended regions of parallel flat membrane bilayers that are stacked over each other, with regions of membrane curvature found only at their edges. Cisternae are better suited for ribosome binding and are enriched in proteins associated with the translocation machinery.
• Tubules are found in the smooth endoplasmic reticulum (SER) and are involved in the synthesis and storage of lipids. ER tubules have high membrane curvature at their cross-section.

Similarities between cisternae and tubules include:

• Both are present within eukaryotic cells.
• They are located in association with the endoplasmic reticulum.
• Both are involved in the synthesis of different molecules.
• Both cisternae and tubules provide passage for the movement of different molecules to their respective destinations.

Comparative Table: Cisternae vs Tubules

The main difference between cisternae and tubules lies in their location within the endoplasmic reticulum (ER) and their functions. Here is a table comparing the two:

Cisternae are found in the rough endoplasmic reticulum and are involved in the packaging and modification of proteins. On the other hand, tubules are found in the smooth endoplasmic reticulum and are involved in the synthesis and storage of lipids.