This proposal will test whether membrane proteins within lipid cubic phases preferentially sit in more or less curved bilayer regions, using our recent advances in preparing cubic phase films with high orientation, combined with 2D Grazing Incidence-SANS. This is a resubmission of previous ISIS proposal RB1710446, for which panel feedback was that it was highly rated, but evidence was requested for availability of the labelled protein OmpF. We now have an e-mail from our collaborators in Newcastle confirming that they will provide labelled and unlabelled OmpF.