1. Quality control of human ABCG2 protein in the endoplasmic reticulum: ubiquitination and proteasomal degradation.
- Author
-
Wakabayashi-Nakao K, Tamura A, Furukawa T, Nakagawa H, and Ishikawa T
- Subjects
- ATP Binding Cassette Transporter, Subfamily G, Member 2, ATP-Binding Cassette Transporters chemistry, ATP-Binding Cassette Transporters genetics, Amino Acid Sequence, Animals, Humans, Molecular Sequence Data, Neoplasm Proteins chemistry, Neoplasm Proteins genetics, Polymorphism, Single Nucleotide, Protein Folding, Protein Stability, Sequence Homology, Amino Acid, ATP-Binding Cassette Transporters metabolism, ATP-Binding Cassette Transporters physiology, Endoplasmic Reticulum metabolism, Neoplasm Proteins metabolism, Neoplasm Proteins physiology, Proteasome Endopeptidase Complex metabolism, Protein Processing, Post-Translational, Ubiquitination
- Abstract
Human ATP-binding cassette (ABC) transporter ABCG2 (BCRP/MXR/ABCP) is a plasma membrane protein carrying intra- and inter-molecular disulfide bonds and an N-linked glycan. Both disulfide bond formation and N-glycosylation are critical check points determining the stability and degradation fate of ABCG2 protein in the endoplasmic reticulum (ER). Misfolded ABCG2 protein without those post-translational modifications is removed from the ER by retrotranslocation to the cytosol compartment, ubiquitination by ubiquitin ligase, and finally degradation by proteasomes. Certain non-synonymous SNP variants of ABCG2 undergo such ER-associated degradation (ERAD).
- Published
- 2009
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