The p53 transcription factor is found in every cell of the body, where it helps to prevent cancer by activating and deactivating the right genes. When the cell is exposed to potentially carcinogenic stress, such as DNA damage or oxygen deficiency, p53 can, for example, switch on the genetic programme for cell death, preventing the cancer from spreading to the rest of the body.
Almost half of all cancer tumours involve a mutation of the gene for p53, and in the hope of developing new cancer therapies, many cancer researchers study the mechanisms the protein controls.
Now, however, scientists at Karolinska Institutet have identified a great many of the proteins that are under the control of p53. Since p53 research has always been conducted at gene level, the study adds an entirely new dimension to our understanding of p53.
“P53 can be likened to a conductor leading a cellular orchestra,” says Professor Klas Wiman, one of the scientists involved in the study. “Whereas we previously knew which instruments, or genes, make up the orchestra, we now have an idea of the music it plays, by which I mean the proteins that the genes express.”
The scientists have compared how the total protein configuration differs between cells with normally functioning p53 and cells lacking the protein. Their analyses show that p53 affects the expression of at least 115 other proteins, 55 of which have so far been identified.
“These proteins have an important part to play in cancer-related functions, such as apoptosis and metastasis, as well as in ageing,” says Professor Wiman. “Many of the mechanisms were previously unknown, and in several cases we can see changes at a protein level only, and not at a gene level. We believe this information to be of value to the development of new therapies.”
Katarina Sternudd | alfa
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