title: Molecular basis for coupling the plasma membrane to the actin cytoskeleton during clathrin-mediated endocytosis.
abstract: Dynamic actin filaments are a crucial component of clathrin-mediated endocytosis when endocytic proteins cannot supply enough energy for vesicle budding. Actin cytoskeleton is thought to provide force for membrane invagination or vesicle scission, but how this force is transmitted to the plasma membrane is not understood. Here we describe the molecular mechanism of plasma membrane-actin cytoskeleton coupling mediated by cooperative action of epsin Ent1 and the HIP1R homolog Sla2 in yeast Saccharomyces cerevisiae. Sla2 anchors Ent1 to a stable endocytic coat by an unforeseen interaction between Sla2's ANTH and Ent1's ENTH lipid-binding domains. The ANTH and ENTH domains bind each other in a ligand-dependent manner to provide critical anchoring of both proteins to the membrane. The C-terminal parts of Ent1 and Sla2 bind redundantly to actin filaments via a previously unknown phospho-regulated actin-binding domain in Ent1 and the THATCH domain in Sla2. By the synergistic binding to the membrane and redundant interaction with actin, Ent1 and Sla2 form an essential molecular linker that transmits the force generated by the actin cytoskeleton to the plasma membrane, leading to membrane invagination and vesicle budding.
authors.affiliation: Cell Biology and Biophysics Unit,  European Molecular Biology Laboratory, 69117 Heidelberg,  Germany.
authors.forename: Michal
authors.initials: M
authors.lastname: Skruzny
authors.forename: Thorsten
authors.initials: T
authors.lastname: Brach
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Ciuffa
authors.forename: Sofia
authors.initials: S
authors.lastname: Rybina
authors.forename: Malte
authors.initials: M
authors.lastname: Wachsmuth
authors.forename: Marko
authors.initials: M
authors.lastname: Kaksonen
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism*; D000199:Actins / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D002966:Clathrin / Q000378:metabolism*; D003598:Cytoskeletal Proteins / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism*; D004705:Endocytosis; D017353:Gene Deletion; D005786:Gene Expression Regulation; D005982:Glutathione Transferase / Q000378:metabolism; D008055:Lipids / Q000737:chemistry; D008954:Models, Biological; D010641:Phenotype; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D033921:Vesicular Transport Proteins / Q000378:metabolism
chemical_list: D000199:Actins; D002966:Clathrin; D003598:Cytoskeletal Proteins; C121319:ENT1 protein, S cerevisiae; D008055:Lipids; C082266:SLA2 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins; D005982:Glutathione Transferase