Production and Purification of Hybrid Ty-VLPs

The self-assembly properties of a protein encoded by the TYA gene of the yeast Ty element can be exploited to produce hybrid Ty-VLPs (virus-like particles) (1 ,2 ). There has been developed a series of expression vectors that allow the construction of Ty fusion genes containing protein coding sequences of interest (see Chapter 24 ). Many different hybrid Ty-VLPs have now been produced that carry additional proteins that range in size from 3 to 42 kDa. These include regions from human immunodeficiency virus-1 (HIV-1) env, pol, tat, rev, nef , and vif genes; influenza virus hemagglutinin; human α-interferon, feline leukemia virus env , and bovine papillomavirus El and E2 (1–5 and unpublished data).