title: Quality control of human ABCG2 protein in the endoplasmic reticulum: ubiquitination and proteasomal degradation.
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).
authors.affiliation: Department of Biomolecular Engineering, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Wakabayashi-Nakao
authors.forename: Ai
authors.initials: A
authors.lastname: Tamura
authors.forename: Tomoka
authors.initials: T
authors.lastname: Furukawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakagawa
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Ishikawa
mesh_terms: D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D000595:Amino Acid Sequence; D000818:Animals; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D020641:Polymorphism, Single Nucleotide; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D017510:Protein Folding; D011499:Protein Processing, Post-Translational; D055550:Protein Stability; D017386:Sequence Homology, Amino Acid; D054875:Ubiquitination
chemical_list: C116614:ABCG2 protein, human; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D009363:Neoplasm Proteins; D046988:Proteasome Endopeptidase Complex