Oral Presentation 2014 International Biophysics Congress

Structural dissection of architecture of caveolar protein coat (#6)

Oleksiy Kovtun 1 , Vikas Tillu 1 , WooRam Jung 1 , Natalya Leneva 1 , Nicholas Ariotti 1 , Kirill Alexandrov 1 , Robert Parton 1 2 , Brett Collins 1
  1. Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
  2. Centre for Microscopy and Microanalysis, University of Queensland, Brisbane, QLD, Australia

Coordinated action of membrane-embedded caveolin and peripheral cavin proteins results in the formation of membrane invaginations called caveolae. Mammalian caveolae play key roles in variety of cell processes1, and structural information is critically needed to understand the molecular mechanisms underlying their formation and organization. Here we structurally dissect the architecture of the cavin coat from the atomic to the supermolecular scale. The assembly starts from selective trimerisation of cavins via their conservative helical domain. Resultant formation of the supercoil trimer induces helical folding in disordered regions and cavin association into rod-shaped subcomplexes. Then cavin rods assemble through side-to-side and end-to-end interactions into striated lattices characteristic for native caveolar coat. Subcomplexes’ anchoring to lipid membranes involves basic regions located in helical portions of cavins and this association is sufficient for producing membrane curvature.

  1. Parton and del Pozo. Caveolae as plasma membrane sensors, protectors and organizers. Nat Rev Mol Cell Biol, 2013