Targeting Polypeptides to Specific Locations

Two populations of ribosomes are evident in cells: free ribosomes (in the cytosol) and bound ribosomes (attached to the ER)
Free ribosomes mostly synthesize proteins that function in the cytosol
Bound ribosomes make proteins of the endomembrane system and proteins that are secreted from the cell
Polypeptide synthesis always begins in the cytosol
synthesis finishes in the cytosol unless the polypeptide signals the ribosome to attach to the ER
Polypeptides destined for the ER or for secretion are marked by a signal peptide
A signal-recognition particle (SRP) binds to the signal peptide

	Created by Brianna Niemeier about 8 years ago

Biology (Chapter 14) Note on Chapter 14 - Bio, created by Brianna Niemeier on 10/11/2016.