HM1.24 is internalized from lipid rafts by Clathrin-mediated endocytosis through interaction with α-adaptin

Naoko Masuyama, Toshio Kuronita, Rika Tanaka, Tomonori Muto, Yuko Hirota, Azusa Takigawa, Hideaki Fujita, Yoshinori Aso, Jun Amano, Yoshitaka Tanaka

研究成果: ジャーナルへの寄稿学術誌査読

119 被引用数 (Scopus)


HM1.24/Bst2/CD317 is a protein highly expressed in multiple myeloma cells and has unique topology with two membrane anchor domains, an NH2-terminal transmembrane domain and a glycosylphosphatidylinositol attached to the COOH terminus. We show here that human HM1.24 is localized not only on the cell surface but also in the trans-Golgi network and/or recycling endosomes, where it resides in detergent-resistant microdomains, lipid rafts. In contrast to other glycosylphosphatidylinositol-anchored proteins, HM1.24 was internalized from lipid rafts on the cell surface by clathrin-mediated endocytosis. Interestingly, a non-canonical tyrosine-based motif, which contains two tyrosine residues, Tyr-6 and Tyr-8, present in the NH2-terminal cytoplasmic tail, was essential for endocytosis through interaction with an α-adaptin, but not μ2-subunit, of the AP-2 complex. Indeed, an appendage domain of α-adaptin was identified as a protein interacting with the cytoplasmic tail of HM1.24. Furthermore, overexpression of the appendage domain of α-adaptin in cells depleted of α-adaptin could rescue the clathrin-mediated endocytosis of HM1.24 but not of the transferrin receptor. Taken together, our findings suggest that clathrin-dependent endocytosis of human HM1.24 from the cell surface lipid rafts is mediated by direct interaction with α-adaptin.

ジャーナルJournal of Biological Chemistry
出版ステータス出版済み - 6月 5 2009

!!!All Science Journal Classification (ASJC) codes

  • 生化学
  • 分子生物学
  • 細胞生物学


「HM1.24 is internalized from lipid rafts by Clathrin-mediated endocytosis through interaction with α-adaptin」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。