The structural and functional analysis of DNA topoisomerases are facilitated by efficient heterologous expression system for both type I and II enzymes from Drosophila melanogaster. The availability of linker-insertional mutants generated in this laboratory will provide a handle to engineer the protein for further biochemical analysis. For type I DNA topoisomerase, we will focus on the analysis of possible biochemical role of the hydrophilic amino terminus, especially the effect of phosphorylation on the enzymatic activity. The biological functions of DNA topoisomerase will be studied by a molecular genetic approach. I mutants generated in our laboratory and they can provide us valuable tools in defining the critical physiological role of DNA topoisomerase I during the growth and development of a multicellular organism.
Students participate in all aspects of the research projects.
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