TY - BOOK ID - 136633578 TI - Mechanisms of ER Protein Import AU - Zimmermann, Richard AU - Lang, Sven PY - 2022 PB - Basel MDPI - Multidisciplinary Digital Publishing Institute DB - UniCat KW - chaperones KW - contact sites KW - endoplasmic reticulum KW - ER-SURF KW - membrane extraction KW - mitochondria KW - protein targeting KW - bimolecular luminescence complementation KW - competition KW - split luciferase KW - membrane proteins KW - protein–protein interactions KW - Sec61 complex KW - Sec63 KW - synthetic peptide complementation KW - TRAP complex KW - ER protein translocase KW - signal peptide KW - protein translocation KW - nascent peptide chain KW - membrane insertion KW - molecular modelling KW - molecular dynamics simulations KW - molecular docking KW - signal peptidase KW - ER translocon KW - signal recognition particle dependent protein targeting KW - Sec61 dependent translocation KW - co-translational translocation KW - inhibitor KW - high throughput screening KW - Sec61 KW - Sec62 KW - folding KW - insertion KW - membrane protein KW - translocon KW - ribosome KW - transmembrane segment KW - lipid droplets KW - peroxisomes KW - PEX3 KW - membrane protein insertion KW - label-free quantitative mass spectrometry KW - differential protein abundance analysis KW - Zellweger syndrome KW - GET KW - protein transport KW - SND KW - SRP KW - EMC KW - positive-inside rule KW - hydrophobicity KW - transmembrane helix KW - signal recognition particle KW - nascent polypeptide-associated complex KW - fidelity KW - cyclotriazadisulfonamide KW - ER quality control KW - DNAJC3 KW - preprotein KW - Sec61 translocon KW - ribosome stalling KW - signal sequence KW - Sec61 translocase KW - NAC KW - n/a KW - protein-protein interactions UR - https://www.unicat.be/uniCat?func=search&query=sysid:136633578 AB - 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. ER -