Applications of a Multicopy Phenotype Approach
A multicopy phenotype approach to identify new regulatory proteins is not without drawbacks. Overexpression of an activity is not a “real life” situation for the cell. Hartwell and coworkers remark that this method, even while conveniently providing the cloned wildtype gene for further analysis, might fool the investigator; overexpression of any activity might give the desired phenotype, or lead to cell death (2). However, there are ways to circumvent these problems and the investigator need only realize that, when using a multicopy phenotype approach, the next obvious step after the identification of an activity will be to determine its role, as a single copy function, in the cell.
KeywordsCapsular Polysaccharide Multicopy Plasmid Methylmethane Sulfonate High Copy Number Plasmid Capsule Synthesis
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