Figure 7

Simultaneous targeting of QDs to two different proteins via Ssp DnaE and Ssp DnaB intein mediated splicing without cross reactivity. Fluorescence images of stage 10 Xenopus embryos injected with (A) the probes QDot₅₈₅-DnaB I_N and DnaE I_C-QDot₇₀₅ and the corresponding RNAs encoding DnaB I_C-memEGFP and Akt-EGFP-DnaE I_N, (B) the probe QDot₆₅₅-DnaB I_N and RNA encoding Akt-EGFP-DnaE I_N or the probe DnaE I_C-QDot₆₅₅ and RNA encoding DnaB I_C-memEGFP. Both QDot585 and QDot705 translocated to the cell membrane in cells derived from the embryo injected with the complementary probes where they colocalized with memEGFP and Akt-EGFP. In contrast, Akt-EGFP and mem-EGFP clearly target to the cell membrane whereas the non-complementary probes, remain diffuse in the cytoplasm, implying that the two inteins do not cross react.