Which option includes examples of integral membrane proteins?

Which option includes examples of integral membrane proteins?

• A. F1 ATPase head
• B. The ATPase rotor
• C. Stalk B
• D. Two of the above

Answer: (D)

Integral membrane proteins are proteins that are permanently attached to the biological membrane and span the entire lipid bilayer. They play crucial roles in various cellular functions such as transport, cell signaling, and maintaining the structural integrity of the cell. The F1 ATPase head and the ATPase rotor are components of the ATP synthase complex, which is embedded in the inner mitochondrial membrane. The ATPase rotor is an integral part of the enzyme, facilitating the production of ATP through oxidative phosphorylation. These components are classified as integral membrane proteins because they are embedded in the lipid bilayer and are essential for the protein's functionality. On the other hand, Stalk B serves as a pivotal connector within the ATP synthase complex but does not span through the lipid bilayer in the same way as the other two components do. Therefore, it isn't classified as an integral membrane protein. Thus, the choice that suggests two of the options includes integral membrane proteins is accurate, as both the F1 ATPase head and the ATPase rotor meet the criteria for being labeled as integral membrane proteins.

Integral membrane proteins are proteins that are permanently attached to the biological membrane and span the entire lipid bilayer. They play crucial roles in various cellular functions such as transport, cell signaling, and maintaining the structural integrity of the cell.

The F1 ATPase head and the ATPase rotor are components of the ATP synthase complex, which is embedded in the inner mitochondrial membrane. The ATPase rotor is an integral part of the enzyme, facilitating the production of ATP through oxidative phosphorylation. These components are classified as integral membrane proteins because they are embedded in the lipid bilayer and are essential for the protein's functionality.

On the other hand, Stalk B serves as a pivotal connector within the ATP synthase complex but does not span through the lipid bilayer in the same way as the other two components do. Therefore, it isn't classified as an integral membrane protein.

Thus, the choice that suggests two of the options includes integral membrane proteins is accurate, as both the F1 ATPase head and the ATPase rotor meet the criteria for being labeled as integral membrane proteins.