title: Influence of isoform-specific Ras lipidation motifs on protein partitioning and dynamics in model membrane systems of various complexity.
abstract: The partitioning of the lipidated signaling proteins N-Ras and K-Ras4B into various membrane systems, ranging from single-component fluid bilayers, binary fluid mixtures, heterogeneous raft model membranes up to complex native-like lipid mixtures (GPMVs) in the absence and presence of integral membrane proteins have been explored in the last decade in a combined chemical-biological and biophysical approach. These studies have revealed pronounced isoform-specific differences regarding the lateral distribution in membranes and formation of protein-rich membrane domains. In this context, we will also discuss the effects of lipid head group structure and charge density on the partitioning behavior of the lipoproteins. Moreover, the dynamic properties of N-Ras and K-Ras4B have been studied in different model membrane systems and native-like crowded milieus. Addition of crowding agents such as Ficoll and its monomeric unit, sucrose, gradually favors clustering of Ras proteins in forming small oligomers in the bulk; only at very high crowder concentrations association is disfavored.
authors.affiliation: Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, Dortmund Technical University, Otto-Hahn-Strasse 4a, D-44227 Dortmund.
authors.forename: Nelli
authors.initials: N
authors.lastname: Erwin
authors.affiliation: Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, Dortmund Technical University, Otto-Hahn-Strasse 4a, D-44227 Dortmund.
authors.forename: Satyajit
authors.initials: S
authors.lastname: Patra
authors.affiliation: Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, Dortmund Technical University, Otto-Hahn-Strasse 4a, D-44227 Dortmund.
authors.forename: Mridula
authors.initials: M
authors.lastname: Dwivedi
authors.affiliation: Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, Dortmund Technical University, Otto-Hahn-Strasse 4a, D-44227 Dortmund.
authors.forename: Katrin
authors.initials: K
authors.lastname: Weise
authors.affiliation: Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, Dortmund Technical University, Otto-Hahn-Strasse 4a, D-44227 Dortmund.
authors.forename: Roland
authors.initials: R
authors.lastname: Winter
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism*; D006801:Humans; D050356:Lipid Metabolism; D008567:Membranes, Artificial; D020033:Protein Isoforms / Q000737:chemistry / Q000378:metabolism; D018631:ras Proteins / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D008567:Membranes, Artificial; D020033:Protein Isoforms; D018631:ras Proteins
keywords: Ras proteins; clustering; crowding; lipoprotein-membrane interaction; model biomembranes; phase-separation