Protein Export and Secretory Pathway Quiz

Signal Recognition Particle (SRP)

• SRP is involved in the targeting of proteins to the endoplasmic reticulum (ER) in the secretory pathway
• SRP binds to the signal peptide of the nascent protein, preventing its translation and allowing the ribosome to target the ER membrane

SRP Components

• The SRP54 subunit is involved in binding to the signal peptide of the nascent protein
• This binding causes a pause in protein synthesis, allowing the ribosome to target the ER membrane

Translocon

• The translocon is a protein complex embedded in the ER membrane that forms a channel for protein translocation
• It facilitates the transport of proteins across the ER membrane, and is involved in the co-translational insertion of proteins into the ER

Signal Peptidase

• Signal peptidase is an enzyme that removes the signal peptide from the nascent protein during protein translocation
• This cleavage event is necessary for the maturation of the protein, allowing it to assume its native conformation and function

Test your knowledge about proteins destined for export and the secretory pathway, including their synthesis on membrane-bound ribosomes and the characteristics of their hydrophobic signal peptide.