Identifying proteins that affect mRNA localization in living cells.

Messenger RNA transport has emerged as a significant mechanism for regulating gene expression. Many of the protein factors affecting RNA transport remain unknown. The emergence of green fluorescent protein (GFP) fluorescence microscopy allows imaging in living cells and an increased understanding of in vivo molecular transport. GFP imaging is now applied to RNA transport by engineering RNA hairpins into the RNA of interest and observing fluorescence from GFP fused to an RNA-binding protein that recognizes the hairpins. In yeast, different genetic backgrounds can be tested to identify various proteins that affect RNA transport and localization. The technology also allows the swapping of different regions of the RNA to determine the cis requirements for transport. GFP RNA imaging opens many possibilities to examine RNA transport in real time in a variety of different organisms. (c) 2002 Elsevier Science (USA).