title: Secretory pathway quality control operating in Golgi, plasmalemmal, and endosomal systems.
abstract: Exportable proteins that have significant defects in nascent polypeptide folding or subunit assembly are frequently retained in the endoplasmic reticulum and subject to endoplasmic reticulum-associated degradation by the ubiquitin-proteasome system. In addition to this, however, there is growing evidence for post-endoplasmic reticulum quality control mechanisms in which mutant or non-native exportable proteins may undergo anterograde transport to the Golgi complex and post-Golgi compartments before intracellular disposal. In some instances, these proteins may undergo retrograde transport back to the endoplasmic reticulum with re-targeting to the endoplasmic reticulum-associated degradation pathway; in other typical cases, they are targeted into the endosomal system for degradation by vacuolar/lysosomal proteases. Such quality control targeting is likely to involve recognition of features more commonly expressed in mutant proteins, but may also be expressed by wild-type proteins, especially in cells with perturbation of local environments that are essential for normal protein trafficking and stability in the secretory pathway and at the cell surface.
authors.affiliation: Division of Endocrinology/Diabetes Center and Department of Developmental/Molecular Biology, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx NY 10461, USA. arvan@aecom.yu.edu
authors.forename: Peter
authors.initials: P
authors.lastname: Arvan
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhao
authors.forename: Jose
authors.initials: J
authors.lastname: Ramos-Castaneda
authors.forename: Amy
authors.initials: A
authors.lastname: Chang
mesh_terms: D000818:Animals; D001692:Biological Transport; D002352:Carrier Proteins / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D011992:Endosomes / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D008954:Models, Biological; D021381:Protein Transport
chemical_list: D002352:Carrier Proteins; D008565:Membrane Proteins