The team, from The University of Texas at Austin, the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany and Ludwig Maximilians University of Munich, reported their findings in Proceedings of the National Academy of Science on July 5.
"We found that the microtubules grow stiffer as they grow longer, a very unusual and surprising result," said Ernst-Ludwig Florin, assistant professor with the Center of Nonlinear Dynamics at The University of Texas at Austin. "This will have a big impact on our understanding of how microtubules function in the cell and on advancing materials research.
"To my knowledge, no manmade material has this property--to become stiffer as it elongates," said Florin. "This research could lead to the design of novel materials based on this biological structure."
Microtubules, which are about 25 nanometers in diameter, play an essential role in many cellular processes, acting as girders of support for the cell and tracks along which organelles--structures in cells that perform specialized functions--can move. They are also essential components of flagella and cilia, the extensions of some cells that give them movement.
Florin and his colleagues measured the stiffness and length of cellular microtubules using a "single-particle tracking" technique. They attached yellow-green fluorescent beads to the tips of microtubules of various lengths and measured the position of the bead by analyzing frame-by-frame videos of the beads moving in solution. (The beads were 250 or 500 nanometers in diameter.)
The changes in the beads' position were used to calculate the stiffness of the filaments they were attached to, through a method recently developed by the theoretical physicists on the research team.
To the surprise of the scientists, they found that the longer the filament, the more rigid it became.
Florin and his coauthors attribute the microtubules' unique properties to their molecular architecture. The nanometer-sized filaments are hollow tubes made of tubulin proteins that bind to each other in ways that give them the ability to be both flexible and stiff. Flexibility is important for microtubules as they grow and change in cells, while rigidity is important when cells need support.
"Microtubules are optimally designed to give the maximum of mechanical performance at a minimum cost for the cell," said Francesco Pampaloni, a physical chemist at EMBL.
The new finding about the microtubules' properties could provide insights into using the filaments as models for the development of nano-materials.
Ernst-Ludwig Florin | EurekAlert!
The search for dark matter widens
21.03.2018 | American Institute of Physics
Scientists have a new way to gauge the growth of nanowires
19.03.2018 | DOE/Argonne National Laboratory
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.
They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...
A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...
For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.
In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...
Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...
On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...
19.03.2018 | Event News
16.03.2018 | Event News
13.03.2018 | Event News
21.03.2018 | Life Sciences
21.03.2018 | Trade Fair News
20.03.2018 | Physics and Astronomy