title: Modeling the interplay between protein and lipid aggregation in supported membranes.
abstract: We present a theoretical model that deals with the complex interplay between lipid segregation and the self-aggregation of lipid-attached proteins. The model, in contrast to previous ones that consider proteins only as passive elements affecting the lipid distribution, describes the system including three terms: the dynamic interactions between protein monomers, the interactions between lipid components, and a mixed term considering protein-lipid interactions. It is used to explain experimental results performed on a well-defined system in which a self-aggregating soluble bacterial cytoskeletal protein polymerizes on a lipid bilayer containing two lipid components. All the elements considered in a previously described protein model, including torsion of the monomers within the filament, are needed to account for the observed filament shapes. The model also points out that lipid segregation can affect the length and curvature of the filaments and that the dynamic behavior of the lipids and proteins can have different time scales, giving rise to memory effects. This simple model that considers a dynamic protein assembly on a fluid and active lipid surface can be easily extended to other biologically relevant situations in which the interplay between protein and lipid aggregation is needed to fully describe the system.
authors: Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain.
authors: Pablo González
authors: PG
authors: de Prado Salas
authors: Instituto de Microelectrónica de Madrid, CSIC, Isaac Newton 8 (PTM), Tres Cantos, E-28760 Madrid, Spain.
authors: Mario
authors: M
authors: Encinar
authors: CIC nanoGUNE Consolider, Tolosa Hiribidea, 76, E-20018 Donostia, San Sebastian, Spain.
authors: Alvaro
authors: A
authors: Alonso
authors: Instituto de Catálisis y Petroleoquímica, CSIC, c/ Marie Curie, 2, Cantoblanco, E-28049 Madrid, Spain; Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia), c/ Faraday 9, Cantoblanco, E-28049 Madrid, Spain. Electronic address: marisela.velez@icp.csic.es.
authors: Marisela
authors: M
authors: Vélez
authors: Departamento de Física Teórica de la Materia Condensada, Condensed Matter Physics Institute (IFIMAC) and Instituto de Ciencia de Materiales Nicolás Cabrera, Universidad Autónoma de Madrid, E-28049 Madrid, Spain.
authors: Pedro
authors: P
authors: Tarazona
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism*; D003598:Cytoskeletal Proteins / Q000737:chemistry* / Q000378:metabolism*; D008563:Membrane Lipids / Q000378:metabolism*; D021962:Membrane Microdomains / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D011485:Protein Binding; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary
chemical_list: D001426:Bacterial Proteins; D003598:Cytoskeletal Proteins; C071525:FtsZ protein, Bacteria; D008563:Membrane Lipids
keywords: Atomic force microscopy; Dynamic protein filaments; Lipid domains; Protein–lipid interactions; Supported bilayers; Theoretical model