STRUCTURAL DETERMINANTS WITHIN THE SUBUNIT PROTEIN OF TY1 VIRUS-LIKE PARTICLES

The fy virus-like particles (VLPs) are functionally analogous to retro viral particles. They package the enzymes and the RNA necessary for re trotransposition, and mediate the integration of the reverse-transcrip tion product into the genome of the host cell. Here we map three struc tural determinants of particle assembly in the subunit protein. We hav e also identified key residues in these regions that seem to be involv ed in subunit interaction and particle morphology. In particular, two point mutations in putative amphipathic helices have remarkable effect s on VLP morphology, increasing the diameter as much as eightfold.