Investigation of the Nucleolar Targeting Signals of DdSrc1 in Dictyostelium Discoideum

The Dictyostelium discoideum protein, DdSrc1, was recently identified. Early studies revealed that Src1 localizes to the nuclear envelope where the nuclear envelope and nucleoli come into contact. There are seven predicted nucleolar localization signals within the protein sequence of Src1. By creating truncated constructs of Src1 to include different combinations of these predicted nucleolar localization signals, the functionality of the signals was investigated using fluorescence microscopy. It was found that signal 4 has the independent functionality to localize to the nucleoli, while signal 3 is not sufficient to independently localize to the nucleoli. Comparison to previous work done with these signals is discussed. Conclusions for all seven signals have still not been drawn, so suggestions for future work with the inconclusive signal are presented.