Biological membranes are like a guarded border. They separate the cell from the environment and at the same time control the import and export of molecules.
The nuclear membrane can be crossed via many tiny pores. Scientists at the Biozentrum and the Swiss Nanoscience Institute at the University of Basel, together with an international team of researchers, have discovered that proteins found within the nuclear pore function similar to a velcro. In “Nature Nanotechnology”, they report how these proteins can be used for controlled and selective transport of particles.
There is much traffic in our cells. Many proteins, for example, need to travel from their production site in the cytoplasm to the nucleus, where they are used to read genetic information. Pores in the nuclear membrane enable their transport into and out of the cell nucleus.
The Argovia Professor Roderick Lim, from the Biozentrum and the Swiss Nanoscience Institute at the University of Basel, studies the biophysical basics of this transport. In order to better understand this process, he has created an artificial model of the nuclear pore complex, together with scientists from Lausanne and Cambridge, which has led to the discovery that its proteins function like a nanoscale “velcro” which can be used to transport tiniest particles.
“Dirty velcro” inside the nuclear pore
Nuclear pores are protein complexes within the nuclear membrane that enables molecular exchange between the cytoplasm and nucleus. The driving force is diffusion. Nuclear pores are lined with “velcro” like proteins. Only molecules specially marked with import proteins can bind to these proteins and thus pass the pore. But for all non-binding molecules the nuclear pore acts as a barrier.
The researchers postulated that transport depends on the strength of binding to the “velcro” like proteins. The binding should be just strong enough that molecules to be transported can bind but at the same time not too tight so that they can still diffuse through the pore.
In an artificial system recreating the nuclear pore, the researchers tested their hypothesis. They coated particles with import proteins and studied their behavior on the molecular “velcro”. Interestingly, the researchers found parallels in behavior to the velcro strip as we know it.
On “clean velcro”, the particles stick immediately. However, when the “velcro” is filled or “dirtied” with import proteins, it is less adhesive and the particles begin to slide over its surface just by diffusion. “Understanding how the transport process functions in the nuclear pore complex was decisive for our discovery,” says Lim. “With the nanoscale ‘velcro’ we should be able to define the path to be taken as well as speed up the transport of selected particles without requiring external energy.”
Potential lab-on-a-chip technology applications
Lim's investigations of biomolecular transport processes form the basis for the discovery of this remarkable phenomenon that particles can be transported selectively with a molecular “velcro”. “This principle could find very practical applications, for instance as nanoscale conveyor belts, escalators or tracks,” explains Lim. This could also potentially be applied to further miniaturize lab-on-chip technology, tiny labs on chips, where this newly discovered method of transportation would make today's complex pump and valve systems obsolete.
Kai D. Schleicher, Simon L. Dettmer, Larisa E. Kapinos, Stefan Pagliara, Ulrich F. Keyser, Sylvia Jeney and Roderick Y.H. Lim
Selective Transport Control on Molecular Velcro made from Intrinsically Disordered Proteins
Nature Nanotechnology; published online 15 June 2014 | doi: 10.1038/nnano.2014.103
Prof. Dr. Roderick Lim, University of Basel, Biozentrum, and Swiss Nanoscience Institute, phone: +41 61 267 20 83, email: email@example.com
http://dx.doi.org/10.1038/nnano.2014.103 - Abstract
Katrin Bühler | Universität Basel
More than just a mechanical barrier – epithelial cells actively combat the flu virus
04.05.2016 | Helmholtz-Zentrum für Infektionsforschung
Discovery of a fundamental limit to the evolution of the genetic code
03.05.2016 | Institute for Research in Biomedicine (IRB Barcelona)
Using an ultra fast-scanning atomic force microscope, a team of researchers from the University of Basel has filmed “living” nuclear pore complexes at work for the first time. Nuclear pores are molecular machines that control the traffic entering or exiting the cell nucleus. In their article published in Nature Nanotechnology, the researchers explain how the passage of unwanted molecules is prevented by rapidly moving molecular “tentacles” inside the pore.
Using high-speed AFM, Roderick Lim, Argovia Professor at the Biozentrum and the Swiss Nanoscience Institute of the University of Basel, has not only directly...
If a person pushes a broken-down car alone, there is a certain effect. If another person helps, the result is the sum of their efforts. If two micro-particles are pushing another microparticle, however, the resulting effect may not necessarily be the sum their efforts. A recent study published in Nature Communications, measured this odd effect that scientists call “many body.”
In the microscopic world, where the modern miniaturized machines at the new frontiers of technology operate, as long as we are in the presence of two...
Researchers from the Max Planck Institute Stuttgart have developed self-propelled tiny ‘microbots’ that can remove lead or organic pollution from contaminated water.
Working with colleagues in Barcelona and Singapore, Samuel Sánchez’s group used graphene oxide to make their microscale motors, which are able to adsorb lead...
Neutron scattering and computational modeling have revealed unique and unexpected behavior of water molecules under extreme confinement that is unmatched by any known gas, liquid or solid states.
In a paper published in Physical Review Letters, researchers at the Department of Energy's Oak Ridge National Laboratory describe a new tunneling state of...
Honeycomb structures as the basic building block for industrial applications presented using holo pyramid
Researchers of the Alfred Wegener Institute (AWI) will introduce their latest developments in the field of bionic lightweight design at Hannover Messe from 25...
27.04.2016 | Event News
15.04.2016 | Event News
12.04.2016 | Event News
04.05.2016 | Physics and Astronomy
04.05.2016 | Physics and Astronomy
04.05.2016 | Materials Sciences