Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study reveals how ‘microbial axolotl’ repairs itself

09.04.2018

In a new study, published in Current Biology this week, a research team from Uppsala University in Sweden reports new insights into the regenerative capabilities of Stentor, a single celled model organism for regeneration biology. The study used novel gene expression methods that allowed the researchers to identify over one thousand genes that are involved in the regeneration process of individual stentor cells.

Some animals, such as the axolotl salamander, can regrow new body parts in a process that involves the generation of new cells. The damaged cells will die off and the limb will regenerate through cell division, which creates new tissue. Single-celled organisms however cannot utilise this strategy, as they only comprise a single cell – hence upon significant damage, they usually die.


Ettema, Thijs J. G. et al. (2018) RNA sequencing of Stentor cell fragments reveals transcriptional changes during cellular regeneration, Current Biology, DO

Uppsala University

Yet, some single-celled organisms, such as the giant ciliate Stentor, have the rare ability to repair themselves when damaged, in a process referred to as ‘self-repair’ or ‘self-regeneration’. Whereas the ability of Stentor to self-regenerate has been known for some time, detailed knowledge about which genes play a role in this process has thus far been lacking. Now, a research team from Uppsala University has identified over a thousand genes that are involved in rebuilding a fully-fledged Stentor cell after being cut into two halves.

The Uppsala research team focused their study on the Stentor polymorphus, a trumpet-shaped ciliate which they could isolate from a pond nearby the laboratory.

“Stentor cells are huge and can be over 1 mm in length, which makes it possible to see single cells with the naked eye without using a microscope,” says Henning Onsbring, doctoral student at the Department of Cell and Molecular Biology, Uppsala University, who was the lead author of the study. “The large size makes Stentor suitable to study when you want to analyse regenerative capacity at the cellular level.”

Stentor cells have a distinct shape, with a mouth part to eat bacteria on one side, and a tail to attach to particles on the other side of the cell. Previous studies had shown that if you cut a Stentor cell in half, each cell fragment will regenerate into a fully functional cell with a mouth and tail.

This means that one half needs to regrow a mouth, while the other half has to regenerate a tail. Using a new method, the Uppsala researchers were able to identify which Stentor genes were involved in regenerating a new mouth, and which genes were responsible for building a new tail.

“The method we used involved the sequencing and quantification of RNA molecules in individual cell fragments, something that was never done before,” says Dr. Thijs Ettema, associate professor at the Department of Cell and Molecular Biology, Uppsala University, who led the study.

“Usually, such methods are only performed on model organisms for which a genome sequence is available. This was not the case for Stentor polymorphus however. We needed to tweak existing protocols and test whether we could use these to study gene expression changes in regenerating Stentor cell fragments.”

Using the newly developed protocol, Onsbring found that many more genes are involved in the regeneration of the mouth part as compared to the tail of the cell.

“The mouth part of the cell is used for feeding and represents a rather large and complex structure. Our results indicate that rebuilding this mouth structure involves roughly ten times as many genes as compared to regenerating the tail part of the cell,” says Onsbring. “We also managed to confirm observations from previous microscopy studies that suggested that cellular regeneration shares similarities with the process of cell division. We found that several genes that were previously implicated in cell division were also upregulated during various stages of regeneration.”

Finally, the Uppsala research team also identified a group of signaling proteins, known as proteins kinases, to be involved in cellular regeneration of stentor cells.

“A previous study had recently reported that the Stentor genome encodes many of these proteins kinase genes. The function of this expanded set of genes was still unclear however. If anything, we now show that many of these protein kinases are expressed during specific stages of the regeneration process. Possibly, the expansion of this group of signaling genes represented an important evolutionary step in the emergence of the ability to perform self-repair,” concludes Ettema.

For more information, please contact: Thijs Ettema, thijs.ettema@icm.uu.se, phone: +46 (0) 70 5384219 (mobile)

Weitere Informationen:

Ettema, Thijs J. G. et al. (2018) RNA sequencing of Stentor cell fragments reveals transcriptional changes during cellular regeneration, Current Biology, DOI: 10.1016/j.cub.2018.02.055
http://www.cell.com/current-biology/fulltext/S0960-9822(18)30240-9

Linda Koffmar, Uppsala University | idw - Informationsdienst Wissenschaft

Further reports about: Biology Molecular Biology cell division fragments microbial proteins regenerating

More articles from Life Sciences:

nachricht AI-driven single blood cell classification: New method to support physicians in leukemia diagnostics
13.11.2019 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Small RNAs link immune system and brain cells
13.11.2019 | Goethe-Universität Frankfurt am Main

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Magnets for the second dimension

If you've ever tried to put several really strong, small cube magnets right next to each other on a magnetic board, you'll know that you just can't do it. What happens is that the magnets always arrange themselves in a column sticking out vertically from the magnetic board. Moreover, it's almost impossible to join several rows of these magnets together to form a flat surface. That's because magnets are dipolar. Equal poles repel each other, with the north pole of one magnet always attaching itself to the south pole of another and vice versa. This explains why they form a column with all the magnets aligned the same way.

Now, scientists at ETH Zurich have managed to create magnetic building blocks in the shape of cubes that - for the first time ever - can be joined together to...

Im Focus: A new quantum data classification protocol brings us nearer to a future 'quantum internet'

The algorithm represents a first step in the automated learning of quantum information networks

Quantum-based communication and computation technologies promise unprecedented applications, such as unconditionally secure communications, ultra-precise...

Im Focus: Distorted Atoms

In two experiments performed at the free-electron laser FLASH in Hamburg a cooperation led by physicists from the Heidelberg Max Planck Institute for Nuclear physics (MPIK) demonstrated strongly-driven nonlinear interaction of ultrashort extreme-ultraviolet (XUV) laser pulses with atoms and ions. The powerful excitation of an electron pair in helium was found to compete with the ultrafast decay, which temporarily may even lead to population inversion. Resonant transitions in doubly charged neon ions were shifted in energy, and observed by XUV-XUV pump-probe transient absorption spectroscopy.

An international team led by physicists from the MPIK reports on new results for efficient two-electron excitations in helium driven by strong and ultrashort...

Im Focus: A Memory Effect at Single-Atom Level

An international research group has observed new quantum properties on an artificial giant atom and has now published its results in the high-ranking journal Nature Physics. The quantum system under investigation apparently has a memory - a new finding that could be used to build a quantum computer.

The research group, consisting of German, Swedish and Indian scientists, has investigated an artificial quantum system and found new properties.

Im Focus: Shedding new light on the charging of lithium-ion batteries

Exposing cathodes to light decreases charge time by a factor of two in lithium-ion batteries.

Researchers at the U.S. Department of Energy's (DOE) Argonne National Laboratory have reported a new mechanism to speed up the charging of lithium-ion...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

High entropy alloys for hot turbines and tireless metal-forming presses

05.11.2019 | Event News

Smart lasers open up new applications and are the “tool of choice” in digitalization

30.10.2019 | Event News

International Symposium on Functional Materials for Electrolysis, Fuel Cells and Metal-Air Batteries

02.10.2019 | Event News

 
Latest News

Magnets for the second dimension

12.11.2019 | Machine Engineering

New efficiency world record for organic solar modules

12.11.2019 | Power and Electrical Engineering

Non-volatile control of magnetic anisotropy through change of electric polarization

12.11.2019 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>