Abstract
The structure of many proteins entering the secretory pathway is dependent on stabilization by disulfide bonds. To support disulfide-linked folding, the endoplasmic reticulum (ER) must maintain a strongly oxidizing environment compared to the highly reduced environment of the cytosol. We report here the identification and characterization of Ero1p, a novel and essential ER-resident protein. Mutations in Ero1p cause extreme sensitivity to the reducing agent DTT, whereas overexpression confers DTT resistance. Strikingly, compromised Ero1p function results in ER retention of disulfide-stabilized proteins in a reduced, nonnative form, while not affecting structural maturation of a disulfide-free protein. We conclude that there exists a specific cellular redox machinery required for disulfide-linked protein folding in the ER and that Ero1p is an essential component of this machinery.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Animals
-
Antioxidants / pharmacology
-
Conserved Sequence
-
Disulfides / metabolism
-
Dithiothreitol / analogs & derivatives
-
Dithiothreitol / pharmacology
-
Endoplasmic Reticulum / chemistry*
-
Endoplasmic Reticulum / drug effects
-
Endoplasmic Reticulum / enzymology
-
Flow Cytometry
-
Fungal Proteins / chemistry
-
Fungal Proteins / metabolism*
-
Gene Expression Regulation, Fungal / physiology
-
Glycoproteins / chemistry
-
Glycoproteins / genetics*
-
Glycoproteins / metabolism
-
Glycoside Hydrolases / chemistry
-
Glycoside Hydrolases / metabolism
-
Humans
-
Male
-
Membrane Glycoproteins*
-
Molecular Sequence Data
-
Mutagenesis / physiology
-
Oxidation-Reduction
-
Oxidoreductases
-
Oxidoreductases Acting on Sulfur Group Donors
-
Protein Folding
-
Saccharomyces cerevisiae / chemistry*
-
Saccharomyces cerevisiae / metabolism*
-
Saccharomyces cerevisiae Proteins*
-
Sequence Homology, Amino Acid
-
beta-Fructofuranosidase
Substances
-
Antioxidants
-
Disulfides
-
Fungal Proteins
-
Glycoproteins
-
Membrane Glycoproteins
-
Saccharomyces cerevisiae Proteins
-
dithiothreitol tetraacetate
-
ERO1A protein, human
-
Oxidoreductases
-
Oxidoreductases Acting on Sulfur Group Donors
-
ERO1 protein, S cerevisiae
-
Glycoside Hydrolases
-
beta-Fructofuranosidase
-
Dithiothreitol