You are hereJuly 9, 2018
New Method Developed for Turning Skin Cells into Pluripotent Stem Cells
Researchers have succeeded in converting skin cells into pluripotent stem cells by activating the cell's own genes. Up till now, reprogramming has only been possible by introducing the critical genes for the conversion, called Yamanaka factors, artificially into skin cells where they are not normally active at all.
The finding opens up new insights into the mechanisms controlling early embryonic gene activation.
The new method was achieved by using gene editing technology, called CRISPRa, that can be directed to activate genes. The method utilizes a blunted version of the Cas9 “gene scissors” that does not cut DNA and can therefore be used to activate gene expression without mutating the genome.
"CRISPR/Cas9 can be used to activate genes. This is an attractive possibility for cellular reprogramming because multiple genes can be targeted at the same time. Reprogramming based on activation of endogenous genes rather than overexpression of transgenes is also theoretically a more physiological way of controlling cell fate and may result in more normal cells. In this study, we show that it is possible to engineer a CRISPR activator system that allows robust reprogramming of iPSC," said Timo Otonkoski, M.D., Ph.D., and professor in the Centre of Excellence in Stem Cell Metabolism at the University of Helsinki, Finland.
An important key for the success was also activating a critical genetic element that was earlier found to regulate the earliest steps of human embryo development after fertilization. "Using this technology, pluripotent stem cells were obtained that resembled very closely typical early embryonal cells," said Juha Kere, M.D., Ph.D.Dr. Kere is professor and group leader at the Department of Biosciences and Nutrition, Karolinska Institutet, Sweden, and a professor in Genetics and Molecular Medicine at King’s College London, UK.
The discovery also suggests that it might be possible to improve many other reprogramming tasks by addressing genetic elements typical of the intended target cell type.
The study is published in Nature Communications.