Most of our work so far has been carried out in cultured cells, because they are easy to image and amenable to streamlined genetic manipulation. The engineering of animals bearing marks in genes of interest would provide us the capability to extend our observations into the native state. Importantly, the configuration of the genes may be better recapitulated in living tissues.
The Singer lab has generated a line of transgenic mice carrying our mRNA reporter system (MS2 hairpin loops and the cognate MS2 capsid protein-GFP) (Park, Lim et al. 2014). We developed other imaging tools in various in vivo contexts, in collaborations with experts at Janelia.
Fluorescent reporter for endogenous Actin mRNA in the soma layer of CA1 neurons of an acute hippocampal slice. Bright spots in the nuclei represent active transcription sites (Park, Lim et al. 2014).