Mechanisms of ER Protein Import

Edited by
May 2022
258 pages
  • ISBN978-3-0365-4094-8 (Hardback)
  • ISBN978-3-0365-4093-1 (PDF)

This book is a reprint of the Special Issue Mechanisms of ER Protein Import that was published in

Biology & Life Sciences
Chemistry & Materials Science
Medicine & Pharmacology

Protein import into the endoplasmic reticulum (ER) is the first step in the biogenesis of approximately 10,000 different soluble and membrane proteins of human cells, which amounts to about 30% of the proteome. Most of these proteins fulfill their functions either in the membrane or lumen of the ER plus the nuclear envelope, in one of the organelles of the pathways for endo- and exocytosis (ERGIC, Golgi apparatus, endosome, lysosome, and trafficking vesicles), or at the cell surface as plasma membrane or secreted proteins. An increasing number of membrane proteins destined to lipid droplets, peroxisomes or mitochondria are first targeted to and inserted into the ER membrane prior to their integration into budding lipid droplets or peroxisomes or prior to their delivery to mitochondria via the ER-SURF pathway. ER protein import involves two stages, ER targeting, which guarantees membrane specificity, and the insertion of nascent membrane proteins into or translocation of soluble precursor polypeptides across the ER membrane. In most cases, both processes depend on amino-terminal signal peptides or transmembrane helices, which serve as signal peptide equivalents. However, the targeting reaction can also involve the ER targeting of specific mRNAs or ribosome–nascent chain complexes. Both processes may occur co- or post-translationally and are facilitated by various sophisticated machineries, which reside in the cytosol and the ER membrane, respectively. Except for resident ER and mitochondrial membrane proteins, the mature proteins are delivered to their functional locations by vesicular transport.

  • Hardback
© 2022 by the authors; CC BY-NC-ND license
chaperones; contact sites; endoplasmic reticulum; ER-SURF; membrane extraction; mitochondria; protein targeting; bimolecular luminescence complementation; competition; split luciferase; membrane proteins; protein–protein interactions; Sec61 complex; Sec63; synthetic peptide complementation; TRAP complex; ER protein translocase; signal peptide; Sec61 complex; protein translocation; nascent peptide chain; membrane insertion; molecular modelling; molecular dynamics simulations; molecular docking; signal peptide; signal peptidase; ER translocon; endoplasmic reticulum; protein targeting; chaperones; protein translocation; signal recognition particle dependent protein targeting; Sec61 dependent translocation; co-translational translocation; endoplasmic reticulum; inhibitor; high throughput screening; Sec61; Sec62; Sec63; protein translocation; endoplasmic reticulum; folding; insertion; membrane protein; translocon; ribosome; transmembrane segment; endoplasmic reticulum; lipid droplets; peroxisomes; PEX3; protein targeting; membrane protein insertion; protein translocation; label-free quantitative mass spectrometry; differential protein abundance analysis; Zellweger syndrome; endoplasmic reticulum; GET; protein targeting; protein transport; SND; SRP; Sec61 complex; EMC; positive-inside rule; hydrophobicity; signal peptide; transmembrane helix; protein targeting; signal recognition particle; nascent polypeptide-associated complex; ribosome; endoplasmic reticulum; membrane proteins; fidelity; co-translational translocation; endoplasmic reticulum; cyclotriazadisulfonamide; ER quality control; DNAJC3; signal peptide; preprotein; Sec61 translocon; ribosome stalling; endoplasmic reticulum; ribosome; signal sequence; signal recognition particle; protein targeting; GET; SND; Sec61 translocase; NAC; n/a