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
Flipping molecular attachments amps up activity of CO2 catalyst
06.10.2015 | DOE/Brookhaven National Laboratory
Safe nanomotors propelled by sugar
06.10.2015 | Max-Planck-Institut für Intelligente Systeme
An interdisciplinary team of researchers has built the first prototype of a miniature particle accelerator that uses terahertz radiation instead of radio...
At present, tiny magnetic whirls – so called skyrmions – are discussed as promising candidates for bits in future robust and compact data storage devices. At...
In cooperation with the Center for Nano-Optics of Georgia State University in Atlanta (USA), scientists of the Laboratory for Attosecond Physics of the Max Planck Institute of Quantum Optics and the Ludwig-Maximilians-Universität have made simulations of the processes that happen when a layer of carbon atoms is irradiated with strong laser light.
Electrons hit by strong laser pulses change their location on ultrashort timescales, i.e. within a couple of attoseconds (1 as = 10 to the minus 18 sec). In...
At the exhibition BATTERY + STORAGE as part of WORLD OF ENERGY SOLUTIONS 2015 in Stuttgart, the Fraunhofer Institutes for Laser Technology ILT and for Ceramic Technologies and Systems IKTS will be showing how laser technology can be used to manufacture batteries both cost- and energy-efficiently.
In the truest sense, it’s all about watts at the Dresden-based Fraunhofer Institute for Ceramic Technologies and Systems IKTS and the Aachen-based Fraunhofer...
01.10.2015 | Event News
30.09.2015 | Event News
17.09.2015 | Event News
06.10.2015 | Information Technology
06.10.2015 | Physics and Astronomy
06.10.2015 | Life Sciences