Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


The fate of cells: protein ensures that primordial germ cells give rise to sperm and egg cells


During the development of an organism, individual cells are directed to perform specific tasks within the body of the adult organism. Researchers at the Cells-in-Motion Cluster of Excellence show now that the function of a certain protein is responsible for the development of sperm and egg cells.

When an embryo develops, single cells acquire specific fates that allow them to perform specific tasks in the adult organism. The primordial germ cells are formed very early in embryonic development and migrate within the embryo to the developing testis or the ovary, where they give rise to sperm and egg cells. During their migration, the germ cells pass through tissues and interact with cells that acquire other specific fates such as muscle, bone or nerve cells in response to different cues.

Primordial germ cells (PGCs, green) in a zebrafish embryo. Right: PGCs lacking the Dead end protein differentiate into somatic cells, here into muscle cells with a characteristic elongated shape.

T. Gross-Thebing et al./Dev Cell

Primordial germ cells, however, ignore those signals and maintain their fate. What are the mechanisms behind this process? Researchers at the Cells-in-Motion (CiM) Cluster of Excellence at the University of Münster have now discovered that a certain protein expressed within the progenitor germ cells is responsible for their fate maintenance: the Dead End protein.

“For the first time, we have been able to demonstrate that germ cells lacking the protein undergo differentiation into other cell types during their migration,” says Theresa Gross-Thebing, lead author of the study and a PhD student at the Cluster of Excellence’s Graduate School.

As a consequence, in embryos lacking the Dead End protein the progenitor germ cells do not give rise to cells critical for reproduction and the adult organism becomes infertile. These findings are also relevant for the understanding of the development of certain germ cell tumours. The study appears in the latest issue of the journal “Developmental Cell”.

The detailed story:

The new results were obtained by studying primordial germ cells in zebrafish embryos. These embryos are transparent and develop rapidly outside the body of the female, allowing the visualization of such processes within the live organism. The researchers in the CiM group headed by Prof. Erez Raz observed progenitor germ cells in which the level of the Dead end protein was reduced. In previous studies, researchers had already discovered that germ cells lacking the Dead End protein had disappeared after one day. It was therefore presumed that these germ cells died during their migration such that they did not arrive at their destination. Following this assumption the protein was named “Dead end”.

To be able to observe the primordial germ cells over a longer period of time than in earlier studies, the researchers from Münster labelled germ cells with fluorescent proteins and employed different microscopy techniques. A type of microscopy that was especially useful in this study is “light-sheet fluorescence microscopy”. This type of microscopy scans the tissue very rapidly layer by layer, while a camera records the fluorescence signal. Next, a composite image of individual layers is generated allowing observation of the three-dimensional tissue structure and the position of cells within it.

By genetically deactivating certain signalling cues, that normally guide primordial germ cells to the correct place, the researchers made these cells migrate into foreign tissues. After one day they were able to recognize that primordial germ cells lacking the Dead End protein obviously changed their shape: the characteristic round shape and the migratory behaviour could not be observed anymore. Instead, the cells displayed shapes typical of the neighbouring somatic cells – for example, an elongated form of a muscle cell or long processes characteristic of nerve cells. In each case, the shape, behaviour and molecular features were matching the tissue in which the cells resided.

After one day only 20 percent of all primordial germ cells lacking Dead End still showed their original shape. After two days, the researchers could no longer observe any cells displaying the shape of a progenitor germ cell. While some of the germ cells were dying, as had been observed in earlier studies, most of them were transformed into other types of cells based on their shape.

Importantly, in addition to the morphological changes, germ cells lacking Dead End function developed into other types of cells as judged by the expression of specific molecules. In contrast with wildtype cells, in the absence of Dead end germ cells started expressing proteins characteristic of muscle or nerve cells. “These results enable us to show for the first time that Dead End as a protein is responsible for maintaining the fate of primordial germ cells,” says Prof. Erez Raz.

These findings are relevant for research concerning certain germ cell tumours in humans, named teratomas. These tumours occur in large part in ovaries or testicles and contain, for example, tissues like teeth or hair. “Previous studies in mice suggest that germ cells lacking Dead End can initiate tumours and that within these tumours somatic differentiation occurs,” says Theresa Gross-Thebing. In future, the researchers want to investigate how Dead end functions in maintenance of germ cell fate and in inhibition of transformation of the cells into cancer cells that can develop into different types of somatic cells. Further studies will determine if the results of this basic research study can find their way into any possible medical applications.

The study received funding from the Cells-in-Motion Cluster of Excellence, the European Research Council (ERC) and the German Research Foundation.

Original publication:

Gross-Thebing T, Yigit S, Pfeiffer J, Reichman-Fried M, Bandemer J, Ruckert C, Rathmer C, Goudarzi M, Stehling M, Tarbashevich K, Seggewiss J, Raz E. The vertebrate protein Dead end maintains primordial germ cell fate by inhibiting somatic differentiation. Dev Cell 2017, DOI: 10.1016/j.devcel.2017.11.019


Svenja Ronge
Cells-in-Motion Cluster of Excellence
Media Relations Manager
Tel: +49 251 83-49310

Weitere Informationen: Prof. Erez Raz

Svenja Ronge | idw - Informationsdienst Wissenschaft

Further reports about: fate germ cells nerve cells primordial germ cells progenitor

More articles from Life Sciences:

nachricht Microscope measures muscle weakness
16.11.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

nachricht Good preparation is half the digestion
16.11.2018 | Max-Planck-Institut für Stoffwechselforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

Latest News

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

NASA keeps watch over space explosions

16.11.2018 | Physics and Astronomy

Science & Research
Overview of more VideoLinks >>>