In a similar way, a cellular waste management system constantly picks up superfluous proteins and damaged organelles in human cells and delivers them to recycling facilities. However, if the cellular waste management system stops working, severe illnesses like Alzheimer´s disease or cancer may develop.
The picture shows the structure of the autophagic scaffold. The scientists used atomic force microscopy to visualize the hight profile of the scaffold on artificial membranes. The protein meshwork rises gradually (yellow-red) from the ground level of the membrane (black) to the crest of the scaffold (white) where it reaches its maximum hight. The resulting two-dimensional map was then projected onto a sphere which represents the autophagosome.
Picture: Thomas Wollert
Copyright: MPI of Biochemistry
Scientists at the Max Planck Institute of Biochemistry in Martinsried near Munich, Germany, recently revealed how a major cellular recycling system – autophagy – works. The results of the study have now been published in the research journal Cell.
The autophagic system in cells captures cellular waste and delivers it to specialized recycling facilities, called lysosomes. Thus autophagy protects the cell from accumulating cell debris. If autophagy slows down or stops working, severe diseases like cancer, Parkinson´s or Alzheimer´s disease may occur.
Much in the same way as trash bags envelop waste, a membrane engulfs cellular debris during autophagy. This molecular “recycling bag” is called autophagosome. After the membrane has been wrapped around the waste, it is transported to lysosomes for degradation. Because lysosomes are also surrounded by membranes, autophagosomes are able to fuse with them to deliver their content without leakage. Finally, an armada of different enzymes degrades the lysosomal content into its basic molecular building blocks.
Cellular waste differs enormously in size and shape, imposing a major challenge for the autophagic system. On the one hand the membrane of autophagosomes needs to be flexible enough to engulf the waste. On the other hand, mechanical stability is needed to guide the membrane around the waste in a zipper-like fashion. Thomas Wollert and his Research Group “Molecular Membrane and Organelle Biology” now revealed the molecular architecture of an autophagic membrane scaffold, which mechanically supports autophagosomes.Small meshes – large effects
Furthermore, the researchers were able to recreate the scaffold on artificial membranes in the test tube and to follow its assembly and disassembly in real time. “It is important that we understand the molecular mechanisms that drive autophagy to be able to modulate its speed”, said Thomas Wollert, MPIB group leader who supervised the study. “If we were able to accelerate autophagy, Alzheimer´s disease and other neurological disorders could perhaps be cured in the future.” [VS]Original Publication:
Anja Konschak | Max-Planck-Institut
Fruit fly studies shed light on adaptability of nerve cells
17.04.2015 | Deutsches Zentrum für Neurodegenerative Erkrankungen e.V. (DZNE)
Rare monkey photographed in Congo's newest national park, Ntokou-Pikounda
17.04.2015 | Wildlife Conservation Society
Astronomers from Chalmers University of Technology have used the giant telescope Alma to reveal an extremely powerful magnetic field very close to a supermassive black hole in a distant galaxy
Astronomers from Chalmers University of Technology have used the giant telescope Alma to reveal an extremely powerful magnetic field very close to a...
A team of physicists from MPQ, Caltech, and ICFO proposes the combination of nano-photonics with ultracold atoms for simulating quantum many-body systems and creating new states of matter.
Ultracold atoms in the so-called optical lattices, that are generated by crosswise superposition of laser beams, have been proven to be one of the most...
According to new research out of the Texas A&M Health Science Center College of Medicine, that is indeed the case. Chetan Jinadatha, M.D., M.P.H., assistant...
Researchers from ICFO, MIT and UC Riverside have been able to develop a graphene-based photodetector capable of converting absorbed light into an electrical voltage at ultrafast timescales
The efficient conversion of light into electricity plays a crucial role in many technologies, ranging from cameras to solar cells.
Electrical charges not only move through wires, they also travel along lengths of DNA, the molecule of life. The property is known as charge transport.
In a new study appearing in the journal Nature Chemistry, authors, Limin Xiang, Julio Palma, Christopher Bruot and others at Arizona State University's...
13.04.2015 | Event News
25.03.2015 | Event News
19.03.2015 | Event News
17.04.2015 | Power and Electrical Engineering
17.04.2015 | Earth Sciences
17.04.2015 | Physics and Astronomy