title: s-Afadin binds more preferentially to the cell adhesion molecules nectins than l-afadin.
abstract: l-Afadin was originally purified from rat brain as an actin filament (F-actin)-binding protein that was homologous to the AF-6 gene product. Concomitantly, s-afadin that did not show an F-actin-binding capability was copurified with l-afadin. Structurally, s-afadin lacks the C-terminal F-actin-binding domain but has two short sequences that were not present in l-afadin. The properties and roles of l-afadin have intensively been investigated, but those of s-afadin have poorly been understood. We show here an additional difference in their biochemical properties other than binding to F-actin between l-afadin and s-afadin. Both l-afadin and s-afadin bound to nectins, immunoglobulin-like cell adhesion molecules, whereas s-afadin more preferentially bound to nectins than l-afadin. The PDZ domain of l-afadin and s-afadin was essential for their binding to nectin-3. The dilute domain of l-afadin negatively regulated its binding to nectin-3, but the deletion of the C-terminal F-actin-binding domain of l-afadin did not increase the binding of l-afadin to nectin-3. These results indicate that the s-afadin-specific C-terminal inserts may be involved in its preference of binding to nectin-3 and raise the possibility that there are proteins other than nectins that more preferentially bind s-afadin than l-afadin.
authors.affiliation: Division of Pathogenetic Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Hyogo, 650-0047, Japan; Division of Molecular and Cellular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Hyogo, 650-0017, Japan.
authors.forename: Reiko
authors.initials: R
authors.lastname: Kobayashi
authors.forename: Souichi
authors.initials: S
authors.lastname: Kurita
authors.forename: Muneaki
authors.initials: M
authors.lastname: Miyata
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Maruo
authors.forename: Kenji
authors.initials: K
authors.lastname: Mandai
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Rikitake
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Takai
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000378:metabolism; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002478:Cells, Cultured; D008810:Mice, Inbred C57BL; D008840:Microfilament Proteins / Q000378:metabolism*; D000075983:Nectins; D009474:Neurons / Q000378:metabolism*; D011485:Protein Binding
chemical_list: D000199:Actins; D015815:Cell Adhesion Molecules; D008840:Microfilament Proteins; C000619017:Nectin3 protein, mouse; D000075983:Nectins; C108835:afadin