Kellis lab reveals surprising role of microRNA

January 10, 2008

EECS Assistant Professor Manolis Kellis and postdoctoral research fellow Alexander Stark have reported in the January 1 issue of the journal Genes & Development that in certain DNA sequences, both strands of a DNA segment can perform useful functions, each encoding a distinct molecule that helps to control cell functions.

While investigating the microRNA pairs in the fruit fly and in mice, Kellis and Stark found that certain RNA genes, known as microRNAs, can sometimes use both DNA strands, instead of just one, to encode RNA. Both resulting microRNAs fold into hairpins that get processed into microRNAs. The significance is that both the 'dye' and the 'mold' in this process appear to have distinct functionality.

As Kellis reported to the MIT News Office, January 9, 2008, 'The idea that there could be such dual-function strands, where both DNA strands encode functional RNA products, "had never even been hypothesized."' Further work has suggested that this may be true for other species as well.

This work, supported in part by grants from the National Institutes of Health and the National Science Foundation, was carried out not in a lab but as a computational challenge "at the computer terminal," according to Kellis.


MIT News Office article, Jan. 9, 2008: "MIT reports new twist in microRNA biology"

"A single Hox locus in Drosophila produces functional microRNAs from opposite DNA strands"