Even though arsenic is toxic for many organs in the human body, it is used in the treatment of some forms of cancer, and it is an active component of drugs against parasitic diseases.
Arsenic is used in therapeutic medicine, but we know relatively little about the mechanisms by which cells develop resistance to arsenic, which may lead to a lower therapeutic effect.
Proteins control cellular processes
Scientist Doryaneh Ahmadpour at the Department of Chemistry and Molecular Biology, University of Gothenburg, has carried out experiments with common baker’s yeast, in order to find out how inflow and outflow take place in cells.
“The knowledge we obtain from determining these mechanisms in yeast can be subsequently used in the long term to produce more effective drugs containing arsenic. A membrane protein known as Fps1 is particularly interesting. This protein transports the trivalent form of arsenic (arsenite) into and out from the cell,” says Doryaneh Ahmadpour.
She has worked with scientist Michael Thorsen to show how the Fps1 protein is regulated and how the inflow into the cell of arsenic is influenced by another protein, Hog1.
The results suggest that a reduction in the activity of Hog1 is an effective way of increasing the ability of the cell to absorb arsenic. This may make the cell more sensitive to arsenic and thus give more effective treatment.
Resistance to arsenic can be increased in a similar manner, by increasing the activity of Hog1, which reduces the inflow of arsenic into the cells.
“We have shown also that a protein known as Slt2 regulates the outflow of arsenic from the cell, and increases the resistance of the cell to arsenic. It is possible, in the same way, to regulate the cellular resistance against arsenic by controlling the activity of Slt2.”
Arsenic as a problem
Arsenic is a toxic metalloid that is naturally found in earth crust. It can be leached out by water or spread by industrial activity.
Arsenic is a global problem due to the increasing contamination of water, soil and crops, not only in the industrialized world but also in developing countries.
“High levels of arsenic in groundwater can lead to humans being exposed to toxic levels in food and water. This affects mainly people in regions in which the crops are watered with arsenic-contaminated water, leading to arsenic being stored in the plants.”
Increased knowledge about arsenic can be used to produce plants with a high absorption, and these can be used to clean contaminated land. The knowledge can also be used to produce food crops, known as “safe crops”, with a limited absorption and storage of arsenic.
The thesis has been successfully defended.For more information, please contact: Doryaneh Ahmadpour, Department of Chemistry and Molecular Biology, University of Gothenburg
Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden
The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
22.09.2017 | Life Sciences
22.09.2017 | Medical Engineering
22.09.2017 | Physics and Astronomy