An international team of biologists has done the seemingly impossible. They’ve revived cell nuclei from a 28,000-year-old frozen woolly mammoth. While the world will have to wait for the first full-blown mammoth resurrection, this could be a big step in that direction. The team’s findings offer researchers hope that ancient DNA, though damaged, could one day be made functional.
The research team salvaged the nuclei from the muscle of “Yuka,” a young woolly mammoth well preserved in Siberian permafrost since the last ice age. They then transplanted them into mouse egg cells. This process, called somatic cell nuclear transfer, is the same one used to clone animals like Dolly the sheep. But unlike for Dolly, the development of those nuclei stopped short of cell division.
After the transfer, researchers observed filling of the transplanted nuclei with mouse proteins—namely, histone and tubulin— and the formation of a new nucleus-like structure. That structure drove the formation of the characteristic spindles that pull genetic material apart during cell division. In the end, the pseudo-nucleus was absorbed by the nucleus of the mouse egg cell.
While the mammoth DNA proved too damaged to follow through with cell division, data indicated that the natural DNA repair machinery of the mouse egg cell lent a helping hand; it tried to reverse at least some of the bruising Yuka’s genetic material sustained while frozen for thousands of years.
And that could be the biggest upshot of the team’s work. Although reviving ancient creatures remains elusive, they’ve demonstrated for the first time that fossilized DNA can be at least partially reawakened.
Woolly mammoth, Yuka, Siberian permafrost, Siberia, cloning, Dolly the sheep, somatic cell nuclear transfer, histone, tubulin, nuclear transfer, mitosis, cell division, fossilized DNA, animal cloning, Scientific Reports