Researchers of CECAD, the Cluster of Excellence at the University of Cologne, Germany, and the Research Institute of Molecular Pathology (IMP) in Vienna, Austria, provide mechanistic insight how muscle assembly is regulated in development and aging.
The present work by Gazda et al demonstrates that UNC-45 establishes a multi-chaperone complex that allows the folding of myosin in a defined array along the thick filament. The cartoon illustrates the “patterned folding” principle, of how UNC-45 composes a protein assembly line that places the chaperone mechanics Hsp70 and Hsp90 (highlighted) at regularly spaced positions to work on the series of motor domains protruding from the myosin filament.
Copyright – please specify: With friendly permission from David Greenlees
The Hoppe lab and others have shown before that the folding of myosin involves the assistance of three molecular chaperones including Hsp70, Hsp90 and a myosin-specific assembly protein called UNC-45. To address the underlying principle of how myosin filaments are formed in muscle cells, Prof. Thorsten Hoppe and his postdoc Wojtek Pokrzywa teamed up with PD Dr. Tim Clausen and his group to perform a detailed structural and physiological analysis of the UNC-45 protein from the soil nematode Caenorhabditis elegans.
The striking findings of this collaboration, published in the scientific journal Cell, revealed that UNC-45 can polymerize into a linear protein chain. As a consequence, multiple binding sites for the myosin substrate as well as for the co-working chaperones Hsp70 and Hsp90 are periodically arranged along the UNC-45 chain. Indeed, this multi-chaperone complex that works on a series of myosin motor domains mimics an industrial assembly line (Fig.1). This mechanism decisively alters the current view of how muscle filaments are formed during development and kept in shape upon aging:(1) The UNC-45 chaperone functions beyond simple nascent protein folding. It represents a novel type of filament assembly factor that provides the molecular scaffold for Hsp70 and Hsp90 chaperones to work at regularly spaced positions on captured client proteins. It will be interesting to see whether this "patterned folding" mechanism is critical for the assembly of other protein filaments.
(2) The Hoppe lab showed before that aberrant UNC-45 function is associated with severe muscle defects resulting in skeletal and cardiac myopathies. Therefore, the discovered mechanism may help to develop strategies against diseases connected with myosin assembly defects.
Gene switch may repair DNA and prevent cancer
12.02.2016 | Institute for Integrated Cell-Material Sciences at Kyoto University
New method opens crystal clear views of biomolecules
11.02.2016 | Deutsches Elektronen-Synchrotron DESY
Today, plants and microorganisms are heavily used for the production of medicinal products. The production of biopharmaceuticals in plants, also referred to as “Molecular Pharming”, represents a continuously growing field of plant biotechnology. Preferred host organisms include yeast and crop plants, such as maize and potato – plants with high demands. With the help of a special algal strain, the research team of Prof. Ralph Bock at the Max Planck Institute of Molecular Plant Physiology in Potsdam strives to develop a more efficient and resource-saving system for the production of medicines and vaccines. They tested its practicality by synthesizing a component of a potential AIDS vaccine.
The use of plants and microorganisms to produce pharmaceuticals is nothing new. In 1982, bacteria were genetically modified to produce human insulin, a drug...
Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock which attains an accuracy which had only been predicted theoretically so far. Their optical ytterbium clock achieved a relative systematic measurement uncertainty of 3 E-18. The results have been published in the current issue of the scientific journal "Physical Review Letters".
Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock...
The University of Würzburg has two new space projects in the pipeline which are concerned with the observation of planets and autonomous fault correction aboard satellites. The German Federal Ministry of Economic Affairs and Energy funds the projects with around 1.6 million euros.
Detecting tornadoes that sweep across Mars. Discovering meteors that fall to Earth. Investigating strange lightning that flashes from Earth's atmosphere into...
Physicists from Saarland University and the ESPCI in Paris have shown how liquids on solid surfaces can be made to slide over the surface a bit like a bobsleigh on ice. The key is to apply a coating at the boundary between the liquid and the surface that induces the liquid to slip. This results in an increase in the average flow velocity of the liquid and its throughput. This was demonstrated by studying the behaviour of droplets on surfaces with different coatings as they evolved into the equilibrium state. The results could prove useful in optimizing industrial processes, such as the extrusion of plastics.
The study has been published in the respected academic journal PNAS (Proceedings of the National Academy of Sciences of the United States of America).
Exceeding critical temperature limits in the Southern Ocean may cause the collapse of ice sheets and a sharp rise in sea levels
A future warming of the Southern Ocean caused by rising greenhouse gas concentrations in the atmosphere may severely disrupt the stability of the West...
12.02.2016 | Event News
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02.02.2016 | Event News
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12.02.2016 | Medical Engineering