Replication and encapsidation of papillomaviruses in Saccharomyces cerevisiae.

Improvements in methodologies to recapitulate and study particular biological functions of the papillomavirus life cycle have led to great advances in our knowledge of these viruses. Described in this chapter are techniques that allow low-copy and high-copy replication of full-length human papillomavirus (HPV) genomes, as well as assembly of virus-like particles, in Saccharomyces cerevisiae (yeast). This system has several distinct advantages that make it an attractive complement to the well-established raft-culturing system. First, yeast are inexpensive, rapid, and simple to culture in the lab. Second, they provide an ever-widening array of genetic tools to analyze HPV functions--most recently notable, the yeast open reading frame (ORF)-deletion library. Third, yeast provide a potentially high-efficiency means to produce large quantities of infectious virus in a short time frame. Fourth, assembly of HPV virus in yeast allows encapsidation of mutant genomes, since previous studies have shown that no viral ORF is required for replication of full-length HPV in yeast.