A fusion protein comprising an N-terminal portion and a C-terminal portion, wherein the N-terminal portion is a heterologous protein of interest which includes membrane proteins and antigens and the C-terminal portion is a polyhedrin targeting peptide which is derived from cypovirus polyhedrin and binds to cypovirus polyhedrin. The polyhedrin targeting peptide is described as a C-terminal portion of cypovirus polyhedrin and as C-terminal portion of cypovirus polyhedrin absent all or part of the N-terminal H1 helix sequence. Vectors and cells capable of expressing the fusion proteins are also provided. The fusion proteins fold with cypovirus polyhedrin to form modified complexes, polyhedra/microcubes useful in myriad applications, including as a platform technology for prophylactic or therapeutic vaccinations, therapeutics and diagnostics, including vaccines, therapeutics and diagnostics etc. employing membrane proteins.