The vault exterior shell is a dynamic structure that allows incorporation of vault-associated proteins into its interior

The Sf9 insect cell expression system is used to form major vault protein (MVP)-only recombinant vaults and a series of protein-mixing experiments are conducted to test whether this particle shell is able to exclude exogenous proteins from interacting with the vault interior. Results demonstrate that the protein shell of the recombinant vault particle is a dynamic structure and suggest a possible mechanism for in vivo assembly of vault-interacting proteins into performed vaults.