Final answer:
SNARE proteins, specifically V-SNARE and T-SNARE, are responsible for mediating the specific fusion of vesicles with target membranes to ensure proper delivery of cellular contents.
Step-by-step explanation:
The set of proteins that mediate specific vesicle and target membrane fusion are known as SNARE proteins. This process is crucial for the trafficking of vesicles within the cell, ensuring they reach their appropriate destinations to maintain cellular function. The V-SNARE (vesicle-SNARE) proteins on the vesicles interact with the complementary T-SNARE (target-SNARE) proteins on the target membranes. When V-SNARE and T-SNARE proteins bind, the vesicle membrane can fuse with the target membrane, delivering the vesicle's contents to the correct location within the cell. This mechanism is essential for processes such as the secretion of proteins and the transport of membrane proteins and lipids to various parts of the cell, including the plasma membrane.