Many scientists have considered using cloning to resurrect extinct animals frozen in permafrost, such as the woolly mammoth. This has proven to be difficult because there are no live cells, and DNA is irreparably damaged by ice crystals.
Now cloning techniques may have progressed to the point where resurrection from permafrost could become reality. Teruhiko Wakayama at the RIKEN Center for Developmental Biology in Kobe and co-workers have produced healthy cloned mice from cells that were frozen for 16 years at -20 °C without any preserving chemicals—simulating the conditions in permafrost (1).
Wakayama and his team adapted a common cloning technique called somatic cell nuclear transfer (SCNT). Usually, researchers collect a single live cell of the donor animal and fuse it with a living egg that has had its own nucleus removed. However dead cells cannot be used for cell fusion, so Wakayama invented a new injection method in which the nuclei from dead cells are directly injected into the egg.
The researchers first performed SCNT on cells from mice frozen for a week. They found that frozen brain cells were the best donor nuclei and, surprisingly, the frozen cell nuclei yielded more healthy clones than living brain cells. It is possible that all the sugars in the brain protect cells from freezing damage. Furthermore, the freezing process might partly unravel the tight bundle of nuclear DNA, allowing the host egg to access the donor’s genetic code more easily.
The normal SCNT procedure failed to produce cloned mice from bodies frozen for 16 years, but the researchers managed to establish embryonic stem cell lines. The stem cell nuclei were injected into other eggs and transferred into surrogate mothers, leading to four healthy cloned mice.
This work represents the first successful cloning from bodies stored in conditions similar to the natural permafrost environment. Wakayama is hopeful that they could eventually produce clones from ancient bodies of extinct species such as mammoths.
“Cells frozen in permafrost for thousands of years are not only frozen but also dried out,” he explains. “This means there is probably more damage in the nuclei than in our 16-year-frozen cells. However, we already published results this year in which we succeeded in using freeze-dried cells for nuclear transfer (2).
“What’s more, our paper demonstrated that even blood cells can be used as nuclear donors. Blood cells are found in any tissue, including skin and bones, which are most likely to be found in permafrost.”
1. Wakayama, S., Ohta, H., Hikichi, T., Mizutani, E., Iwaki, T., Kanagawa, O. & Wakayama, T. Production of healthy cloned mice from bodies frozen at -20 °C for 16 years. Proceedings of the National Academy of Sciences 105, 17318–17322 (2008).
2. Ono, T., Mizutani, E., Li, C. & Wakayama, T. Nuclear transfer preserves the nuclear genome of freeze-dried mouse cells. The Journal of Reproduction and Development In press. (2008)
The corresponding author for this highlight is based at the RIKEN Laboratory for Genomic Reprogramming
Saeko Okada | ResearchSEA
Study shines light on brain cells that coordinate movement
26.06.2017 | University of Washington Health Sciences/UW Medicine
New insight into a central biological dogma on ion transport
26.06.2017 | Aarhus University
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine
Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...
19.06.2017 | Event News
13.06.2017 | Event News
13.06.2017 | Event News
26.06.2017 | Life Sciences
26.06.2017 | Physics and Astronomy
26.06.2017 | Information Technology