MicroRNAs: An emerging portrait
The Human Genome as an RNA Machine
On a wall in Thomas Tuschl's Rockefeller University lab hangs a huge painting created by a street artist. The large, bright figures wearing white lab coats and nametags are members of the Tuschl lab, circa 2004. In the background of the painting, drawings on a green chalkboard illustrate a simplified rendering of the RNA interference pathway. In a 15th floor lab overlooking the East River between Manhattan and Brooklyn, the 2007 version of this group (about a dozen researchers) continues to decipher the mysteries of microRNAs (miRNAs).
Today, scientists have worked out many general properties of miRNAs in the plants, animals, and viruses that encode them. Double-stranded RNA molecules are cleaved by enzymes, including Drosha and Dicer, into mature miRNAs of about 22 nucleotides each. These miRNAs suppress expression of target messenger ...
