Meiosis is a specialized cell division process required to generate gametes, the reproductive cells of an organism. During meiosis, paternal and maternal chromosomes duplicate, pair, and exchange parts of their DNA in a process called meiotic recombination. In order to mediate this exchange of genetic material, cells introduce double strand breaks (DSBs) into their chromosomal DNA. Scientists from the lab of Franz Klein from the Department of Chromosome Biology at the Max Perutz Labs, a joint venture of the University of Vienna and the Medical University of Vienna, have now discovered that cells sometimes liberate DNA fragments at sites of paired, or double, DSBs. Whilst this presents an obvious risk of germline mutations as a consequence of erroneous repair or of integration of fragments from elsewhere at break sites, it may also be a source of evolutionary diversity. The study is published as a research article in Nature.
The new Master’s course in "Molecular Precision Medicine" is concerned with how diseases develop and how to treat them on a molecular and mechanistic level. The course, jointly organised by the Medical Universi-ty of Vienna and University of Vienna, combines scientists from the fields of basic research as well as translational and clinical research and furnishes students with comprehensive knowledge about the poten-tials, challenges, and future prospects of precision medicine. Students can now apply at: www.meduniwien.ac.at/master-mpm.
Changes in daylength are a well-established annual timing cue for animal behavior and physiology. An international collaboration of scientists led by Kristin Tessmar-Raible at the Max Perutz Labs now shows that, in addition to daylength, marine bristle worms sense seasonal intensity changes of UVA/deep violet light to adjust the levels of important neurohormones and their behavior. The study is published in Nature Ecology and Evolution.
Autophagy, from the Greek for ‘self-eating’, is an essential process that isolates and recycles cellular components under conditions of stress or when resources are limited. Cargoes such as misfolded proteins or damaged organelles are captured in a double membrane-bound compartment called the autophagosome and targeted for degradation. A fundamental question concerns precisely how these “garbage bags” form in the cell. Scientists led by Sascha Martens from the Max Perutz Labs, a joint venture of the University of Vienna and the Medical University of Vienna, have now reconstructed the first steps in the formation of autophagosomes. They show that tiny vesicles loaded with the protein Atg9 act as the seed from which the autophagosome emerges. The study is published in Science.
Scientists led by Javier Martinez from the Max Perutz Labs, a joint venture of the Medical University of Vienna and the University of Vienna, have identified a unique chemical reaction at the end of RNA molecules for the first time in human cells. This reaction was previously only observed in bacteria and viruses. Tracing its source among thousands of proteins, they discovered that an unexpected culprit, an enzyme called ANGEL2, executes this reaction. ANGEL2 may play a key role in regulating the response to cellular stress, and possibly in the pathogenesis of neurodegenerative and metabolic diseases. The study is published in “Science”.