title: Functional characterization of Val60, a key residue involved in the membrane-oligomerization of fragaceatoxin C, an actinoporin from Actinia fragacea.
abstract: Actinoporins are pore-forming toxins produced by different sea anemones that self-assemble within the membranes of their target cells and compromise their function as a permeability barrier. The recently published three-dimensional structures of two oligomeric complexes formed by fragaceatoxin C point to Val60 as a key residue involved in the oligomerization of the functional pore. To gain insight into the mechanism of toxin oligomerization, different point mutations have been introduced at this position. Functional characterization of the muteins suggests that Val60 represents a hot-spot where the introduction of mutations hinders protein assembly and reduces the overall affinity for membranes.
authors.affiliation: Biophysics Unit (CSIC, UPV/EHU), University of the Basque Country, P.O. Box 644, 48080 Bilbao, Spain; Department of Biochemistry and Molecular Biology, University of the Basque Country, P.O. Box 644, 48080 Bilbao, Spain; Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, Minato-ku 108-8639, Tokyo, Japan.
authors.forename: Koldo
authors.initials: K
authors.lastname: Morante
authors.affiliation: Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, Minato-ku 108-8639, Tokyo, Japan.
authors.forename: Jose M M
authors.initials: JM
authors.lastname: Caaveiro
authors.affiliation: Biophysics Unit (CSIC, UPV/EHU), University of the Basque Country, P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: Ana Rosa
authors.initials: AR
authors.lastname: Viguera
authors.affiliation: Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, Minato-ku 108-8639, Tokyo, Japan; Medical Proteomics Laboratory, Institute of Medical Science, The University of Tokyo, Minato-ku 108-8639, Tokyo, Japan; Department of Medical Genome Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Minato-ku 108-8639, Tokyo, Japan.
authors.forename: Kouhei
authors.initials: K
authors.lastname: Tsumoto
authors.affiliation: Department of Biochemistry and Molecular Biology, University of the Basque Country, P.O. Box 644, 48080 Bilbao, Spain. Electronic address: juanmanuel.gonzalez@ehu.es.
authors.forename: Juan Manuel
authors.initials: JM
authors.lastname: González-Mañas
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002151:Calorimetry; D003064:Cnidarian Venoms / Q000737:chemistry*; D008969:Molecular Sequence Data; D058105:Polymerization; D012615:Sea Anemones / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid; D014633:Valine / Q000737:chemistry / Q000502:physiology*
chemical_list: D003064:Cnidarian Venoms; C545670:fragaceatoxin C; D014633:Valine
keywords: Lipid–protein interaction; Model membranes; Pore-forming toxins; Protein oligomerization