Results from the FSU study, which includes contributions from researchers at three other institutions, are described in a paper published in the October 7, 2008, edition of PLoS Biology, a peer-reviewed journal that showcases biological science research of exceptional significance. So prodigious were the findings that the current paper -- "Global Reorganization of Replication Domains During Embryonic Stem Cell Differentiation" -- is focused solely on results observed in the mouse embryonic stems cells; data on the human cells will be detailed in a future report.
"We know that all the information (DNA) required to take on the identity of any tissue type is present in every cell, because we already can, albeit very inefficiently, create whole animals from adult
tissue through cloning," Gilbert said. "We also can make a kind of artificial embryonic stem cells, called induced pluripotent stem cells, out of many adult cell types, but there are two major hurdles remaining. First, the methods currently used rely on the unnatural retroviral insertion of genes into patients' cells, and these genes are capable of forming tumors. Second, this method is very inefficient as well because only one in 1,000 cells into which the genes are inserted becomes pluripotent. We must learn how cells lose pluripotency in the first place so we can do a better job of reversing the process without risks to patients.
"The challenge is, adult cells are highly specialized and over the course of their family history over many generations they've made decisions to be certain cell types rather than others," he said. "In doing so, they have tucked away the information they no longer need on how to become other cell types. Hence, all cells contain the same genetic information in their DNA, but during differentiation they package it with proteins int
|Contact: David Gilbert|
Florida State University