Researcher(s)
- Arwen Portilla, Biological Sciences, University of Delaware
Faculty Mentor(s)
- Jeremy Bird, Biological Sciences, University of Delaware
Abstract
DeaD is a protein belonging to the DeaD box family of RNA helicases in Escherichia coli (E. coli). When the E. coli cells are exposed to cold shock conditions, DeaD expression is upregulated, leading to an alternative name, cold shock DeaD box protein A (CsdA). We want to explore the function of DeaD during E. coli growth under cold shock conditions. Prior research has shown that cells with the DeaD gene deleted (ΔdeaD) cannot grow in cold temperatures. I used spot dilution assays to show that the ΔdeaD cold shock phenotype can be rescued by overexpression of DeaD from a plasmid. In addition to assessing the functions of DeaD as a cold shock protein, we also want to characterize the localization of DeaD within the cell. By fusing the DeaD protein with a fluorescent protein, we can use microscopy to track protein localization inside the cell. We examined DeaD localization in our ∆DeaD strain and MG1655 wild-type E. coli as a control. Both strains of cells were transformed with ATC inducible plasmids encoding either GFP or mCherry fluorescent protein fused with DeaD. Both MG1655 and ∆DeaD transformed with GFP-DeaD show puncta when visualized with the microscope; however, more puncta were observed in the ∆DeaD cells. The puncta on these are also brighter than the ones observed in wild-type cells. Based on our preliminary results, we have concluded that functioning DeaD is necessary for cells to survive cold shock conditions and for this localization to occur.