Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The Cellular Trash Bag

13.01.2016

In autophagy, the process responsible for recycling waste in cells, molecular waste bags are produced. As now reported in Nature Communications, scientists at the Max Planck Institute of Biochemistry in Martinsried have identified a molecular glue that sticks small lipid vesicles, the building blocks for the waste bags, together. Autophagy helps cancer cells survive chemotherapy treatment. This is why a glue inhibitor the scientists have recently identified could provide the basis for a new form of cancer treatment.

Autophagy plays an important role in the cellular recycling process. It transports unwanted or damaged cytoplasmic material to the lysosomes, the cells’ recycling plants.


Two Atg9-vesicles (orange) are tethered by the Atg1-kinase complex (blue S-shaped structure). The vesicles are the raw material for a cellular trash bag.

Thomas Wollert © MPI of Biochemistry

This is achieved by producing specialized waste bags, termed autophagosomes, that recognize the waste material, encase it, and transfer it to the recycling plant. Two protein components are essential for the production of these specialized waste bags. One of these is Atg9, a membrane protein embedded in small membrane vesicles, a kind of globule encased in a lipid membrane.

Atg9 vesicles serve as building blocks for the autophagosome waste bag. The second component, the Atg1 kinase complex, is a large protein complex consisting of five subunits. The scientists have now unraveled how both components are involved in the production of the autophagosome.

The scientists reproduced artificial Atg9 vesicle, the starting material for the waste bags, in a test tube. “By adding the Atg1 kinase complex we were able to show that one Atg1 kinase complex binds two Atg9 molecules, thus acting as a kind of clamp and connecting two Atg9 vesicles,” explains Yijian Rao, a member of the Molecular Membrane and Organelle Biology group headed by Thomas Wollert.

In the absence of waste two subunits of the Atg1 kinase complex can block the Atg9 binding site, thus inhibiting vesicle connections, which in turn prevents the formation of autophagosome waste bags. “This means the various subunits of the Atg1 kinase control membrane tethering and the production of the waste bag,” Rao further explains.

A small peptide that bears therapeutic potential is crucial for the medical application of the findings. The researchers were able to show that a certain peptide inhibits the Atg1 kinase complex in yeast cells. As Atg1 and Atg9 appear in both yeast cells and human cells the scientists assume that a similar compound can inhibit autophagy in human cells.

Cancer cells use autophagy in order to survive chemotherapy. Current cancer drugs induce damage in the cancer cells in order to kill them. The downside of the treatment is that such drugs not only attack cancer but also healthy cells.

One way to make cancer cells more vulnerable is to inactivate autophagy. “The inhibitor of the autophagic glue prevents the production of the waste bags and stops autophagy with high precision. This peptide could provide the basis for the development of a new anti-cancer drug or improve the efficiency of chemotherapeutic drugs currently in use,” Rao summarizes.

Original publication:
Rao, Y., Perna, M.B., Hofmann, B., Beier, V., Wollert, T.: The Atg1-kinase complex tethers Atg9-vesicles to initiate autophagy. Nature Communications, January 12, 2016
Doi: 10.1038/NCOMMS10338

Contact:
Dr. Thomas Wollert
Molecular Membrane and Organelle Biology
Max-Planck-Institut für Biochemie
Am Klopferspitz 18
82152 Martinsried
Germany
E-Mail: wollert@biochem.mpg.de
www.biochem.mpg.de/wollert

Dr. Christiane Menzfeld
Public Relations
Max Planck Institute of Biochemistry
Am Klopferspitz 18
82152 Martinsried
Germany
Tel. +49 89 8578-2824
E-Mail: pr@biochem.mpg.de
www.biochem.mpg.de

Weitere Informationen:

http://www.biochem.mpg.de - homepage max planck institute of biochemistry
http://www.biochem.mpg.de/wollert - homepage research group Thomas Wollert

Dr. Christiane Menzfeld | Max-Planck-Institut für Biochemie

Further reports about: Biochemie Membrane autophagy cancer cells human cells kinase complex vesicle

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 >>>