A tale of a tail: Structural insights into the conformational properties of the polyglutamine protein ataxin-3

► ESI-IMS-MS has been used to characterise ataxin-3 (14Q). ► Ataxin-3 (14Q) shows an array of conformational states. ► The C-terminal domain is largely responsible for its conformational flexibility. ► The dimerisation interface of ataxin-3 is likely to be within the Josephin domain.