Researchers have uncovered how a second set of regulators fit into stem cell research, it has been announced.

Whitehead member Richard Young and colleagues have been able to map parts of the embryonic stem cell circuitry and have now discovered how microRNAs fit into the pattern.

MicroRNAs are responsible for aiding cells, whether they self-renew or morph into something different, Eurkalert noted.

"By understanding how master transcription factors turn microRNAs on and off, we now see how these two groups of gene regulators work together to control the state of the cell," said Mr Young, who is senior author of the study published in the August 8th issue of Cell.

The research was conducted by creating genome-wide maps of human and mouse embryonic stem cells that pinpoint where transcription factors bind to DNA and launch gene expression.

Scientists found that one set of microRNA genes was actively expressed in embryonic stem cells while the other set was silenced by other gene regulatory proteins known as Polycomb proteins.

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