Researchers at the University of Edinburgh have discovered that the distinctive species – which has become popular in recent years as a domestic pet – shares with humans the same genetic mechanism that enables embryonic stem cells to divide without limit. This process, which gives embryonic stem cells the capacity to become any of the 200 cell types in the body, is fundamental to all research in the discipline.
Until now, stem cells have been obtained from mice, primates and humans, but never from amphibians. But, because the African clawed frog is easier to study than mice and humans, the Edinburgh team anticipate that it will become an important research tool in their quest to understand and, ultimately, treat disease using stem cells. The results of their study are published in the current edition of the journal Development(*).
The key protein in humans, called Oct4, which governs the process of unlimited division of stem cells, has an equivalent in the African clawed frog, called PouV. This new research shows that the two proteins are not only similar, but perform the same function - both bind to DNA and activate certain genes that keep stem cells dividing. Indeed, embryonic stem cells lacking the Oct4 protein stop dividing and become specialised.
In the study, Dr Gillian Morrison introduced frog PouV proteins into mouse embryonic stem cells lacking Oct4 and found that the frog proteins “rescued” the stem cells – in other words, the cells recovered their ability to divide without limit. Dr Morrison obtained similar effects when she introduced PouV proteins from another amphibian, the axolotl (a type of salamander).
To find out exactly what function PouV proteins perform in frog embryos, Dr Morrison injected special compounds into very young embryos, to inactivate the native PouV proteins. These embryos continued to grow, but had defective heads and tails.
When the scientists looked closely at these embryos, they found that cells had become specialised before they were supposed to – before the embryo was ready for them. Consequently, the structures they make are severely affected.
This suggests that the PouV proteins are holding the cells in an uncommitted state, waiting for the time to come when they will decide what type of cell they are going to be. This is probably what Oct4 is doing in mouse and human embryonic stem cells.
The findings are also interesting because they highlight that the remarkable capacity of embryonic stem cells to divide without limit is at least 300 million years old. “It was very exciting, and humbling, to find that the proteins from such an ancient animal such as the frog can rescue the behaviour of ‘modern’ mouse embryonic stem cells. It told us so much about where this behaviour comes from, and how long ago,” said Dr Morrison.
Dr Josh Brickman, group leader at the Institute for Stem Cell research says, “Our results show that mammals have adopted the function of the amphibian PouV proteins to maintain their embryonic stem cells. These features of dividing without limit and giving rise to many types of cell are thus ancient features of early embryonic cells, crucial for the correct development of both frogs and humans.”
Ana Coutinho | alfa
Flow of cerebrospinal fluid regulates neural stem cell division
21.05.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt
Chemists at FAU successfully demonstrate imine hydrogenation with inexpensive main group metal
21.05.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
Cardiovascular tissue engineering aims to treat heart disease with prostheses that grow and regenerate. Now, researchers from the University of Zurich, the Technical University Eindhoven and the Charité Berlin have successfully implanted regenerative heart valves, designed with the aid of computer simulations, into sheep for the first time.
Producing living tissue or organs based on human cells is one of the main research fields in regenerative medicine. Tissue engineering, which involves growing...
A team of scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg investigated optically-induced superconductivity in the alkali-doped fulleride K3C60under high external pressures. This study allowed, on one hand, to uniquely assess the nature of the transient state as a superconducting phase. In addition, it unveiled the possibility to induce superconductivity in K3C60 at temperatures far above the -170 degrees Celsius hypothesized previously, and rather all the way to room temperature. The paper by Cantaluppi et al has been published in Nature Physics.
Unlike ordinary metals, superconductors have the unique capability of transporting electrical currents without any loss. Nowadays, their technological...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
18.05.2018 | Power and Electrical Engineering
18.05.2018 | Information Technology
18.05.2018 | Information Technology