title: Single molecular dynamic interactions between glycophorin A and lectin as probed by atomic force microscopy.
abstract: Glycophorin A (GpA) is one of the most abundant transmembrane proteins in human erythrocytes and its interaction with lectins has been studied as model systems for erythrocyte related biological processes. We performed a force measurement study using the force mode of atomic force microscopy (AFM) to investigate the single molecular level biophysical mechanisms involved in GpA-lectin interactions. GpA was mounted on a mica surface or natively presented on the erythrocyte membrane and probed with an AFM tip coated with the monomeric but multivalent Psathyrella velutina lectin (PVL) through covalent crosslinkers. A dynamic force spectroscopy study revealed similar interaction properties in both cases, with the unbinding force centering around 60 pN with a weak loading rate dependence. Hence we identified the presence of one energy barrier in the unbinding process. Force profile analysis showed that more than 70% of GpAs are free of cytoskeletal associations in agreement with previous reports.
authors.affiliation: Laboratory of Biodynamics, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Midori-ku, Yokohama, Kanagawa 226-8501, Japan.
authors.forename: Chao
authors.initials: C
authors.lastname: Yan
authors.forename: Alexandre
authors.initials: A
authors.lastname: Yersin
authors.forename: Rehana
authors.initials: R
authors.lastname: Afrin
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sekiguchi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ikai
mesh_terms: D006021:Glycophorins / Q000737:chemistry*; D006801:Humans; D037102:Lectins / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs
chemical_list: D006021:Glycophorins; D037102:Lectins