Send to printer »

GEN News Highlights : Oct 25, 2006

454 Sequencing™ Reveals New Pathway in RNAi

Application by Cold Spring Harbor Laboratory yields insights on DNA methylation.
Research on small RNAs conducted by Cold Spring Harbor Laboratory has revealed the dual role of the Argonaute 4 protein (AGO4) in RNA-directed DNA methylation, reports 454 Life Sciences. The 454 Sequencing™ was used to elucidate the small RNAs associated with AGO4 and the AGO1 protein.

"Small RNAs have emerged as a means of genetic control that were completely unsuspected only 10 years ago," points out Gregory Hannon, Ph.D., of Cold Spring Harbor Laboratory, who led the research. “What we are now finding is that the diversity of small RNAs in many systems is even greater than previously suspected. The new study shows this in Arabidopsis (a model plant), where small RNAs have a major role in controlling the epigenetic organization of the entire genome.

"Conventional DNA sequencing methods gave us glimpses of the various classes of small RNAs that exist in plants and animals. However, only with 454 Sequencing have we been able to fully appreciate the extent of small RNA populations and the breadth of biological processes they might affect,” adds Dr. Hannon.

The study, entitled, "Distinct Catalytic and Non-Catalytic Roles of ARGONAUTE4 in RNA-directed DNA Methylation," which describes a method for obtaining a comprehensive view of the total small RNAs from a single sample, was published in Nature.