Information on proteins is critical for understanding how cells function in health and disease. But while regular proteins are easy to extract and study, it is far more difficult to gather information about membrane proteins, which are responsible for exchanging elements essential to our health, like copper, between a cell and its surrounding tissues.
Now Prof. Nir Ben-Tal and his graduate students Maya Schushan and Yariv Barkan of Tel Aviv University's Department of Biochemistry and Molecular Biology have investigated how a type of membrane protein transfers essential copper ions throughout the body. This mechanism, Schushan says, could also be responsible for how the body absorbs Cisplatin, a common chemotherapy drug used to fight cancer. In the future, this new knowledge may allow scientists to improve the way the drug is transferred throughout the body, she continues.
Their breakthrough discovery was detailed in a recent issue of PNAS (Proceedings of the National Academy of Sciences).
Cellular gatekeepers and chaperones
Most proteins are water soluble, which allows for easy treatment and study. But membrane proteins reside in the greasy membrane that surrounds a cell. If researchers attempt to study them with normal technology of solubilization in water, they are destroyed — and can't be studied.
Copper, which is absorbed into the body through a membrane protein, is necessary to the healthy functioning of the human body. A deficiency can give rise to disease, while loss of regulation is toxic. Therefore, the cell handles copper ions with special care. One chaperone molecule delivers the copper ion to an "entrance gate" outside the cell; another chaperone then picks it up and carries it to various destinations inside the cell.
The researchers suggest that this delicate system is maintained by passing one copper ion at a time by the copper transporter, allowing for maximum control of the copper ions. "This way, there is no risk of bringing several copper ions into the protein at the same time, which ultimately prevents harmful chemical reactions between the ions and the abundant chemical reagents within the cell," explains Prof. Ben-Tal. Once the ion has passed through the transporter into the cell, the transporter is ready to receive another copper ion if necessary.
Improving cancer drugs — and more
The mechanism which transfers copper throughout the body may also be responsible for the transfer of the common chemotherapy drug Cisplatin. By studying how copper is transferred throughout the body, researchers may also gain a better understanding of how this medication and others are transferred into the cell.
With this information, says Prof. Ben-Tal, scientists could improve the transfer of the drug throughout the body, or develop a more effective chemotherapy drug. And that's not the only pharmaceutical dependent on the functioning of membrane proteins. "Sixty percent of drugs target membrane proteins," he explains, "so it's critical to learn how they function."
This work was done in collaboration with Prof. Turkan Haliloglu from Bogazici University, Istanbul.
George Hunka | EurekAlert!
Nanotubes are beacons in cancer-imaging technique
23.05.2016 | Rice University
More light on cancer
20.05.2016 | Lomonosov Moscow State University
A biological and energy-efficient process, developed and patented by the University of Innsbruck, converts nitrogen compounds in wastewater treatment facilities into harmless atmospheric nitrogen gas. This innovative technology is now being refined and marketed jointly with the United States’ DC Water and Sewer Authority (DC Water). The largest DEMON®-system in a wastewater treatment plant is currently being built in Washington, DC.
The DEMON®-system was developed and patented by the University of Innsbruck 11 years ago. Today this successful technology has been implemented in about 70...
Permanent magnets are very important for technologies of the future like electromobility and renewable energy, and rare earth elements (REE) are necessary for their manufacture. The Fraunhofer Institute for Mechanics of Materials IWM in Freiburg, Germany, has now succeeded in identifying promising approaches and materials for new permanent magnets through use of an in-house simulation process based on high-throughput screening (HTS). The team was able to improve magnetic properties this way and at the same time replaced REE with elements that are less expensive and readily available. The results were published in the online technical journal “Scientific Reports”.
The starting point for IWM researchers Wolfgang Körner, Georg Krugel, and Christian Elsässer was a neodymium-iron-nitrogen compound based on a type of...
In the Beyond EUV project, the Fraunhofer Institutes for Laser Technology ILT in Aachen and for Applied Optics and Precision Engineering IOF in Jena are developing key technologies for the manufacture of a new generation of microchips using EUV radiation at a wavelength of 6.7 nm. The resulting structures are barely thicker than single atoms, and they make it possible to produce extremely integrated circuits for such items as wearables or mind-controlled prosthetic limbs.
In 1965 Gordon Moore formulated the law that came to be named after him, which states that the complexity of integrated circuits doubles every one to two...
Characterization of high-quality material reveals important details relevant to next generation nanoelectronic devices
Quantum mechanics is the field of physics governing the behavior of things on atomic scales, where things work very differently from our everyday world.
When current comes in discrete packages: Viennese scientists unravel the quantum properties of the carbon material graphene
In 2010 the Nobel Prize in physics was awarded for the discovery of the exceptional material graphene, which consists of a single layer of carbon atoms...
24.05.2016 | Event News
20.05.2016 | Event News
19.05.2016 | Event News
27.05.2016 | Awards Funding
27.05.2016 | Life Sciences
27.05.2016 | Life Sciences