Lighting up the Doors

Many plant mRNAs can move cell-to-cell or long-distance to execute a non-cell-autonomous function. However, little is known about the mechanism underlying the intracellular sorting of these mobile mRNAs. Our recent publication shows that mobile mRNAs are selectively targeted to plasmodesmata (PD) for cell-to-cell movement. We exploited a fluorescence-based mRNA labeling system to visualize intracellular trafficking of mobile mRNAs in living plant cells. The ex vivo mRNA imaging reveals that mobile but not non-mobile mRNAs are selectively targeted to PD, which suggests that PD-targeting of mRNA is a critical step to determine mRNA cell-to-cell movement.