Regulation of Gene Expression by Small RNAs

New Findings Revolutionize Concepts of Gene FunctionEndogenous small RNAs have been found in various organisms, including humans, mice, flies, worms, fungi, and bacteria. Furthermore, it''s been shown that microRNAs acting as cellular rheostats have the ability to modulate gene expression. In higher eukaryotes, microRNAs may regulate as much as 50 p