Presentation description

The ESCRT pathway is a membrane remodeling pathway that plays a key role in many cell functions such as cytokinesis and protein transport but is also hijacked by viruses for budding. RetroCHMP3, is a newly discovered protein in New World monkeys and mice that has been shown to selectively inhibit viral budding while maintaining host ESCRT processes. One of the functions of the ESCRT pathway is retrotransposition, the insertion of transcribed RNA back into the genome. Interestingly, retroCHMP3 has been found to inhibit retrotransposition in cell lines. It is still unknown the extent of evolutionary impact inhibition of retrotransposition has on the fitness of retroCHMP3. In this study, we hypothesize that when tested in Saccharomyces cerevisiae, the results will show that retroCHMP3 inhibits retrotransposition induced by the Zorro3 LINE-1 retrotransposition element. We will also test the effect of the knockout of an ESCRT III subunit, VPS24, on retrotransposition in the presence of various CHMP3 constructs. This is significant because retroCHMP3 had to undergo retrotransposition to evolve into the gene as we know it today and although it is less cytotoxic than some of the other proteins we are using, it still delays things like cytokinetic abscission. Since retroCHMP3 is thought to also inhibit retrotransposition, this study allows us to start looking into whether retrotransposition is really an evolutionary advantage or not and why it may happen.