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 world
20.11.2017 | Washington University in St. Louis

nachricht Carefully crafted light pulses control neuron activity
20.11.2017 | University of Illinois at Urbana-Champaign

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Water world

20.11.2017 | Life Sciences

Less is more to produce top-notch 2D materials

20.11.2017 | Materials Sciences

Carefully crafted light pulses control neuron activity

20.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>