Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Freiburg Biologists Explain Function of Pentagone

28.06.2016

Study shows how the protein controls the development of fruit fly wings

How do the cells in a human embryo know where they are located in the body and how they should develop? Why do certain cells form a finger while others do not? Freiburg biologists have explained the mechanisms that control these steps by showing why veins form at particular points in the wing of a fruit fly.


Co-receptors (red) are located on the surfaces of the cells. Pentagone causes the co-receptors to become internalised and degraded within the cell (yellow/green).

Image: Research Group Pyrowolakis

The protein Pentagone spreads a particular signal in the wing that tells the cells how to behave. “The proteins Dpp and Pentagone, which are crucial for this developmental step in the organism Drosophila melanogaster, are also present in a similar form in humans,” says the Freiburg biologist Dr. Giorgos Pyrowolakis. “The fundamental principles elucidated in this study are also active in humans, where they might control things like where cells form fingers.”

Pyrowolakis and a team including Jennifer Gawlik, Dr. Mark Norman, Alexander Springhorn, and Robin Vuilleumier published their findings in the journal eLife. In the future, the results could contribute to our understanding of the origin of developmental disorders.

The protein Dpp is located in a cellular field in various concentrations. The cells located in the middle of the future wing produce Dpp. The protein spreads to the rest of the cells in the tissue, becoming less concentrated in the process.

In mathematical terms, this phenomenon is referred to as a concentration gradient. A cell activates different genes depending on where it is located in the gradient. Each cell develops as specified by the genes activated in it, and veins develop when certain thresholds have been reached. Hence, the gradient determines the distance between the veins of the fruit fly wing.

The cells located furthest from the Dpp source produce Pentagone. Without this protein, there would be no concentration gradient in the cell network and Dpp would stuck at the point of its production. If the gene for Pentagone is switched off in fruit flies, the wings of the insects are smaller and the external vein is missing. “Pentagone causes Dpp to keep spreading,” explains Pyrowolakis, “thus extending the distribution-range of the protein.”

The Freiburg biologists elucidated the molecular mechanisms behind these processes in their study. Dpp binds to receptors located on the surface of the cell in the future wing and initiates a signal cascade in the cell. The signal cascade activates different genes depending on how many receptors are bound by Dpp. Pentagone binds to a particular part of the receptors, the so-called co-receptors. They function like tentacles, “grabbing” proteins and passing them on to the receptor.

Pentagone causes the co-receptors to be pushed into the cell to be broken down. This reduces the amount of co-receptors that can bind and pass on Dpp on the cell, causing the receptors to be less active. The concentration gradient of Pentagone is opposite than that of Dpp. The closer a cell is located to the point where Pentagone is produced, the less Dpp it can bind. The amount of Pentagone is adjusted to match that of Dpp. “When the wing grows, the Dpp gradient also expands,” says Pyrowolakis. “Pentagone regulates the gradient in a similar way a thermostat adjusts the temperature.”

Giorgos Pyrowolakis is a research group leader at the Institute of Biology I, Department of Developmental Biology, of the University of Freiburg, a member of the Freiburg Cluster of Excellence BIOSS Centre for Biological Signalling Studies, and a principal investigator at the Spemann Graduate School of Biology and Medicine (SGBM). Jennifer Gawlik is a member of his research group and a member of the SGBM. Robin Vuilleumier and Alexander Springhorn are former members of Pyrowolakis’s research group. Springhorn was also a member of the SGBM. The primary author of this study, Mark Norman, was a postdoctoral researcher in the group. His project was funded by BIOSS.

Original publication:
Mark Norman, Robin Vuilleumier, Alexander Springhorn, Jennifer Gawlik, Giorgos Pyrowolakis (2016). Pentagone internalises glypicans to fine-tune multiple signalling pathways. eLife. DOI: 10.7554/eLife.13301

Contact:
Dr. Giorgos Pyrowolakis
BIOSS Centre for Biological Signalling Studies
University of Freiburg
Phone: +49 (0)761/203-8459
E-Mail: georgios.pyrowolakis@biologie.uni-freiburg.de

Weitere Informationen:

https://www.pr.uni-freiburg.de/pm/2016/pm.2016-06-28.97-en

Rudolf-Werner Dreier | Albert-Ludwigs-Universität Freiburg im Breisgau

More articles from Life Sciences:

nachricht Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

nachricht How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>