Molecular probes and peptide-based cellular delivery for imaging RNA in living cells

Nitin Sharma
Gang Bao Lab
Laboratory of Molecular Bioengineering
Georgia Tech


The detection, imaging and quantification of gene expression in living cells can provide essential information on basic biology and disease processes. To establish this capability, we need to develop biophysical probes and cellular delivery methods to detect specific mRNA in live cells with potential for in vivo applications. In this research work, a major focus is on development of biophysical probes (molecular beacons) and biochemical approaches (peptides etc.) to deliver such probes to different cellular compartments (cytoplasm and nucleus). These approaches are employed to study the expression and localization of mRNAs, co-localization of mRNAs with cytoplasmic organelles and cytoskeleton and co-localization of two RNA molecules in nucleus of living cells. Further using these tools in combination with biophysical approaches such as FRAP and FLIP, dynamics of endogenous RNA in living cells are studied. These studies highlight the organization of RNA macromolecules and their dynamics in living cells. In addition to optical probes, studies have been carried out to develop a potential MRI based molecular switch to detect oligonucleotide hybridization events. In this direction, I will present our early stage efforts aimed at development of functionalized iron oxide nanoparticles for deep-tissue imaging, optimization of coatings to enhance the contrast and some potential strategies for contrast generation to detect hybridization events.