Study shows micro-rna's can move

DURHAM, N.C., April 21 (UPI) -- U.S. and Swedish scientists say they've discovered tiny bits of genetic material known as microRNAs can move from one cell to another.

MicroRNAs were first characterized during the early 1990s as regulating the activity of genes within cells. Now researchers at the Duke Institute for Genome Sciences & Policy, in collaboration with the Universities of Helsinki and Uppsala, have shown microRNAs can move from one cell to another to send signals that influence gene expression on a broader scale.

The scientists said they made the discovery while investigating the intricate details of plant root development in Arabidopsis, a highly studied mustard plant. Although the researchers haven't determined how the microRNAs travel, they said it appears the mobility allows them to play an important developmental role in sharpening the boundaries that define one plant tissue from another.

"To our knowledge, this is the first solid evidence that microRNAs can move from one cell to another," Professor Philip Benfey, director of the Duke IGSP Center for Systems Biology, said.

The finding adds microRNAs to the list of mobile molecules -- including hormones, proteins and other forms of small RNA -- that allow essential communication between cells in the process of organ development.

The study, which included scientists from the Boyce Thompson Institute for Plant Research at Cornell University, appears in the early online edition of the journal Nature.