To fulfill their different functions, proteins have to acquire the correct three-dimensional structure. In other words, polypeptides have to fold first. Molecular chaperones, a diverse group of conserved proteins, have specialized to assist other proteins during their folding.
Toxic protein aggregates can cause neurodegenerative diseases (red: membrane of the cell, blue: interior of the cell, green: toxic aggregates).
Picture: Heidi Olzscha / Copyright: MPIB
If the chaperones fail, misfolding and aggregation of the newly synthesized and pre-existing proteins might occur. In the worst case, this results then in neurodegenerative diseases, such as Alzheimer’s, Huntington’s chorea or Parkinson’s. Alzheimer’s disease, for example, develops because the A-beta and tau proteins aggregate, which leads to neuronal dysfunction and cell death. According to Alzheimer Forschung Initiative e. V., approximately 1.2 million people suffer from this disease only in Germany. The risk to fall ill grows with increasing age.
Scientists in the Department of Cellular Biochemistry at the Max Planck Institute of Biochemistry, headed by F.-Ulrich Hartl, now established a novel experimental model aimed at elucidating cellular protein misfolding and discovered why the misfolding and aggregation are deleterious for cells. They prepared several artificial aggregating proteins without any biological function and introduced them into cells. These model proteins clumped together, coaggregating many natural proteins and, in that way, disturbing their function. By means of quantitative proteomics, the researchers discovered that the affected proteins share certain structural characteristics which predispose them for the co-aggregation: They are large in size, less hydrophobic and show a significant increase of disorder in their structure.
“These are proteins that have not only many, but also very important functions in the cell”, explains Martin Vabulas. “For instance, they are responsible for the stability of the cytoskeleton, the organization of the chromatin in nucleus, the transcription of DNA to RNA or the synthesis of proteins. Simultaneous disturbance of several of these essential processes is most probably the reason of the cellular break-down. As a consequence, protein misfolding diseases develop.”Molecular chaperones could possibly prevent this dire scenario. They are able to shield the aggregates, so that the aggregates cannot get in touch with other proteins anymore. The scientists hope that their new insights might help to develop novel therapeutic strategies in the battle against neurodegenerative diseases, especially at the earlier stages, before the irreversible collapse of cellular protein network sets in.
Zap! Graphene is bad news for bacteria
23.05.2017 | Rice University
Discovery of an alga's 'dictionary of genes' could lead to advances in biofuels, medicine
23.05.2017 | University of California - Los Angeles
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...
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...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.
In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...
Dental plaque and the viscous brown slime in drainpipes are two familiar examples of bacterial biofilms. Removing such bacterial depositions from surfaces is...
23.05.2017 | Event News
22.05.2017 | Event News
17.05.2017 | Event News
23.05.2017 | Life Sciences
23.05.2017 | Medical Engineering
23.05.2017 | Life Sciences