title: Atomic force microscopy studies of interaction of the 20S proteasome with supported lipid bilayers.
abstract: The 20S proteasome plays important roles in degradation of intracellular proteins. Mechanisms of its activation, its localization in cells, and its binding to biomembranes are not well understood. In this study, we used atomic force microscopy (AFM) to investigate interactions between the 20S proteasome and supported bilayers of various lipids in a buffer. We found that the 20S proteasome specifically bound to supported bilayers containing phosphatidylinositol (PI), but did not bind to supported bilayers containing phosphatidylcholine, phosphatidic acid or dioleoyltrimethylammonium propane. Binding of the 20S proteasomes had a high orientation; almost all were in a top view position. The specific and orientational binding of the 20S proteasome with PI may play important roles inside cells such as endoplasmic reticulum (ER) membrane. Use of AFM to study supported bilayers provides new information on ligand-receptor interactions.
authors.affiliation: Division of Materials Science, Graduate School of Science and Engineering, Shizuoka University, Japan.
authors.forename: Shou
authors.initials: S
authors.lastname: Furuike
authors.forename: Junya
authors.initials: J
authors.lastname: Hirokawa
authors.forename: Shinpei
authors.initials: S
authors.lastname: Yamada
authors.forename: Masahito
authors.initials: M
authors.lastname: Yamazaki
mesh_terms: D000818:Animals; D002417:Cattle; D002462:Cell Membrane / Q000378:metabolism*; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D008051:Lipid Bilayers / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D009097:Multienzyme Complexes / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex
chemical_list: D008051:Lipid Bilayers; D009097:Multienzyme Complexes; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex