Researchers at UC, San Francisco developed a novel way of finding out the role of DNA-relatives called microRNA. These molecules are known to turn genes on and off and appear to regulate whether embryonic stem cells remain as stem cells or develop into mature cell types, but learning which genes are controlled by each microRNA has been a challenge. Using this screen, the researchers found 14 microRNAs that speed up cell division; of those, five are commonly found in human embryonic stem cells.
Researchers at UC, San Francisco identified a molecule that regulates differentiation of embryonic stem cells. In some cases, small molecules of the genetic material RNA have the ability to turn genes on and off rather than carrying out the normal RNA function of coding for proteins. These small RNAs, called micro RNA or miRNA, are thought to be one way the cell regulates genes that control how stem cells differentiate into mature cell types. In this study, the researchers created genetically altered mouse embryonic stem cells that lack the miRNA DGCR8.