title: Spectrin-ankyrin interaction mechanics: A key force balance factor in the red blood cell membrane skeleton.
abstract: As major components of red blood cell (RBC) cytoskeleton, spectrin and F-actin form a network that covers the entire cytoplasmic surface of the plasma membrane. The cross-linked two layered structure, called the membrane skeleton, keeps the structural integrity of RBC under drastically changing mechanical environment during circulation. We performed force spectroscopy experiments on the atomic force microscope (AFM) as a means to clarify the mechanical characteristics of spectrin-ankyrin interaction, a key factor in the force balance of the RBC cytoskeletal structure. An AFM tip was functionalized with ANK1-62k and used to probe spectrin crosslinked to mica surface. A force spectroscopy study gave a mean unbinding force of ~30 pN under our experimental conditions. Two energy barriers were identified in the unbinding process. The result was related to the well-known flexibility of spectrin tetramer and participation of ankyrin 1-spectrin interaction in the overall balance of membrane skeleton dynamics.
authors: Innovation Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan. Electronic address: saito_m@bio.c.u-tokyo.ac.jp.
authors: Masakazu
authors: M
authors: Saito
authors: Innovation Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan.
authors: Takahiro
authors: T
authors: Watanabe-Nakayama
authors: Innovation Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan.
authors: Shinichi
authors: S
authors: Machida
authors: Depertment of Life Science, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, B-2 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan.
authors: Toshiya
authors: T
authors: Osada
authors: Innovation Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan; Biofrontier Center, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan.
authors: Rehana
authors: R
authors: Afrin
authors: Innovation Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan.
authors: Atsushi
authors: A
authors: Ikai
mesh_terms: D017487:Ankyrins / Q000737:chemistry / Q000378:metabolism*; D004910:Erythrocyte Membrane / Q000737:chemistry*; D006801:Humans; D019563:Mechanics; D018625:Microscopy, Atomic Force; D008958:Models, Molecular; D013049:Spectrin / Q000737:chemistry / Q000378:metabolism*
chemical_list: D017487:Ankyrins; D013049:Spectrin
keywords: Ankyrin; Dynamic force microscopy; Membrane skeleton; Protein–protein interaction; Spectrin