The discovery suggests that the tiny motor protein is much more important than previously thought – and for humans it may even hold a key to understanding potentially fatal conditions such as aneurisms.
Says Professor Knight of the University’s Faculty of Biological Sciences: “This is an astonishing discovery. Myosin 2’s function is to make the smooth muscle in internal organs tense and relax involuntarily. These creatures have completely different regulatory mechanisms: the myosin in a turkey’s gizzards allows it to ‘chew’ food in the absence of teeth, while that in a scallop enables it to swim. Yet they have exactly the same structure.”
Myosin molecules generate tension in smooth muscle by adhering to form a filament, which grabs hold of a neighbouring filament, and relaxes by letting go. When the muscle is in a relaxed state, myosin molecule folds itself up into a compact structure.
This folded structure allows the smooth muscles to adjust to being different lengths so they can operate over a large distance, such as the bladder or the uterus expanding and contracting. In contrast, skeletal muscles operate over a narrow range, defined by how much joints can move.
Professor Knight says: “We were puzzled to find that the scallop’s myosin 2 had retained its ability to fold and unfold, as they don’t need to accommodate a large range of movement. After all, the scallop only moves its shell a little when it swims.
“In evolution, if something is not essential to the survival of an organism, it is not conserved. The fact that the scallop has retained all the functions of its myosin 2 over hundreds of millions of years tells us that this folding is of fundamental functional importance in muscle and that we don’t know as much about it as we need to know.”
In humans, any changes in the composition of myosin within the muscles can be fatal. For example, a swelling in the walls of an artery can cause a brain aneurism, while an enlarged heart can lead to cardiac arrest in a young, fit person.
Says Professor Knight: “Because these malfunctions occur in our internal organs, we are often unaware of what is going wrong until it’s too late. Learning how to control myosin, how to move it around without disturbing the delicate balance between filaments and individual molecules, is an emerging area and one we are only just beginning to tackle.”
The research, funded by BBSRC, is published in the US journal Proceedings of the National Academy of Sciences (PNAS).
Jo Kelly | alfa
Molecular libraries for organic light-emitting diodes
24.04.2017 | Goethe-Universität Frankfurt am Main
Fine organic particles in the atmosphere are more often solid glass beads than liquid oil droplets
21.04.2017 | Max-Planck-Institut für Chemie
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
24.04.2017 | Life Sciences
24.04.2017 | Earth Sciences
24.04.2017 | Machine Engineering