λN-GFP:: An RNA reporter system for live-cell imaging

We describe a GFP- based RNA reporter system ( gimel(N)- GFP) to visualize RNA molecules in live mammalian cells. It consists of GFP fused to an arginine- rich peptide derived from the phage gimel N protein, gimel(N22), which binds a unique minimal RNA motif and can be used to tag any RNA molecule. gimel(N)- GFP uses a small and easy to engineer RNA tag, reducing the likelihood of perturbing the function of the tagged RNA molecule.