Use of the MS2 aptamer and coat protein for RNA localization in yeast: A response to "MS2 coat proteins bound to yeast mRNAs block 5' to 3' degradation and trap mRNA decay products: implications for the localization of mRNAs by MS2-MCP system".

The MS2 system has been extensively used to visualize single mRNA molecules in live cells and follow their localization and behavior. In their Letter to the Editor recently published, Garcia and Parker suggest that use of the MS2 system may yield erroneous mRNA localization results due to the accumulation of 3' decay products. Here we cite published works and provide new data which demonstrate that this is not a phenomenon general to endogenously expressed MS2-tagged transcripts, and that some of the results obtained in their study could have arisen from artifacts of gene expression.