Signal sequences target proteins for secretion FIGURE 9-24 Proteins destined to be secreted from the cell have an amino-terminal sequence that is rich in hydrophobic residues. This signal sequence binds to proteins in the endoplasmic reticulum (ER) membrane that draw the remainder of the protein through the lipid bilayer. The signal sequence is cleaved from the protein in this process by an enzyme called signal peptidase (not shown). Once inside the endoplasmic reticulum, the protein is directed to the cell membrane, from which it will be secreted. ER lumen Signal sequence- Cytosol ER membrane

Signal sequences target proteins for secretion FIGURE 9-24 Proteins destined to be secreted from the cell have an amino-terminal sequence that is rich in hydrophobic residues. This signal sequence binds to proteins in the endoplasmic reticulum (ER) membrane that draw the remainder of the protein through the lipid bilayer. The signal sequence is cleaved from the protein in this process by an enzyme called signal peptidase (not shown). Once inside the endoplasmic reticulum, the protein is directed to the cell membrane, from which it will be secreted. ER lumen Signal sequence- Cytosol ER membrane

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter31: Completing The Protein Life Cycle: Folding, Processing, And Degradation

Section: Chapter Questions

Problem 9P

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