1h0a: Difference between revisions

Clathrin-mediated endocytosis involves cargo selection and membrane, budding into vesicles with the aid of a protein coat. Formation of, invaginated pits on the plasma membrane and subsequent budding of vesicles, is an energetically demanding process that involves the cooperation of, clathrin with many different proteins. Here we investigate the role of the, brain-enriched protein epsin 1 in this process. Epsin is targeted to areas, of endocytosis by binding the membrane lipid, phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P(2)). We show here that, epsin 1 directly modifies membrane curvature on binding to PtdIns(4,5)P(2), in conjunction with clathrin polymerization. We have discovered that, formation of an amphipathic alpha-helix in epsin is coupled to, PtdIns(4,5)P(2) binding. Mutation of residues on the hydrophobic region of, this helix abolishes the ability to curve membranes. We propose that this, helix is inserted into one leaflet of the lipid bilayer, inducing, curvature. On lipid monolayers epsin alone is sufficient to facilitate the, formation of clathrin-coated invaginations.

1H0A is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] with DIO and I3P as [http://en.wikipedia.org/wiki/ligands ligands]. Structure known Active Site: DI1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1H0A OCA].  

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