Co-expression of a retrotransposon and re-targeted restriction factor impairs yeast growth.

Retrotransposons and retroviruses shape genome evolution and can negatively impact genome function. Saccharomyces cerevisiae minimizes replication of Ty1 family retrotransposons using an inhibitory protein identical to the C-terminal domain of the transposon's capsid protein. We previously elucidated the molecular basis of restriction and subfamily specific targeting and engineered a re-targeted restriction factor. Here, we report that co-expression of the Ty1' retrotransposon and a variant of its restriction factor mutated to re-target a related transposon subfamily impairs yeast growth.