Hi there,

Plasmid curing in yeast is a simple and convenient way to test gene essentiality (in yeast for instance by cloning the wt gene on a URA3 plasmid and deleting the genomic copy by cassette insertion, you can then show the FOA sensitivity of the strain if the gene is essential). You can also test the impact of gene variants on the cell fitness (on the conditional deletion mutant constructed, you introduce a second plasmid encoding the variant to test and test it on FOA). These are the usual experiments in yeast and they are still relevant provided you make the full set of controls for the experiments.

Hope it helps

For industrial biotechnology it is favourable to use plasmid-free strains. Plasmid is a risk-fator for development/win of resistences.

It is definitely significant to study a phenotype by plasmid borne gene. The phenotype should be reversed when the plasmid is cured - pointing that the phenotype is only due to the plasmid borne gene.