60 // DISCOVERY | SCIENCE
THE SCIENCE BEHIND THE PRIZE AUTHOR // SOPHIE BURGESS, SAI CAMPBELL, LAM TRAN, HARRY CARR Each year in October, students, researchers and STEM professionals tune in for the awarding of one of the highest honours in the science community: the Nobel Prize. In the categories of physiology or medicine, chemistry and physics, scientists are presented with these awards in recognition for their exemplary contributions to their respective fields of science. This year, nine accomplished scientists were awarded Nobel Prizes and joined the ranks of extraordinary past Nobel Laureates such as Marie Curie, Alexander Fleming and Albert Einstein. So, who were these scientists and what did they discover? Find out below from ANU’s own next generation of scientists and engineers! Nobel Prize in Physiology or Medicine Many organisms require oxygen to create energy in a process called aerobic respiration. Although we have been familiar with the importance of oxygen for a long time, our understanding of how individual cells adapt to changes in the availability of oxygen has been limited. In 2019, the Nobel Prize for Medicine was awarded to William G. Kaelin Jr, Sir Peter J. Ratcliffe and Gregg L. Semenza for their ground-breaking discovery on ‘how cells sense and adapt to oxygen availability’. The result of their research has opened new doors on promising and exciting new ways to treat a variety of diseases, such as anaemia and cancer. Kaelin, Ratcliffe and Semenza’s combined work led to the identification of key regulatory protein structures and genes, which demonstrate an oxygen sensing mechanism on a molecular basis. Semenza examined the gene responsible for the production of the hormone erythropoietin (EPO), which mediates the production of red blood cells. He discovered that vicinal segments of DNA were involved in regulating the response to changes in oxygen levels. Ratcliffe’s group also studied this gene and both teams found this mechanism to be present in essentially all tissues, such as muscle and fat. Semenza discovered a key oxygen-dependant protein called the hypoxia-inducible factor (HIF) that controlled this response. Kaelin, a cancer researcher studying von Hippel-Lindau disease (VHL) which involves a dramatic increase in the risk of cancer, discovered that the VHL gene was linked to an overproduction of oxygen-regulated proteins. This gene was then found to physically interact with HIF in a process that regulates our oxygen-sensing mechanism.
As a consequence of their research, our understanding of how oxygen levels influence integral physiological processes has greatly expanded. Oxygen-sensing is fundamental to the finetuning of metabolism in muscles, the immune system, foetal growth and the development of new blood cells. More importantly, a failure to detect levels of oxygen is related to a number of diseases, such as cancer. Cancerous cells can take advantage of the systems that are controlled by oxygen to trick the body into growing blood vessels to supply a growing tumour. Because of Kaelin, Ratcliffe and Semenza’s research, intense effort is directed towards the development of drugs that will interfere with oxygen-sensing mechanisms to treat these diseases. Sai Campbell, Bachelor of Philosophy (Biochemistry) Nobel Prize in Physics The Nobel Prize in Physics this year is dedicated to astrophysics: a very interesting field that is perhaps almost as overused in science fiction as quantum mechanics is! The 2019 prize was recently announced on October 8 by the Royal Swedish Academy of Sciences, with the winners being James Peebles, Michel Mayor and Didier Queloz. James Peebles was awarded half of the price for ‘theoretical discoveries in physical cosmology’, with Michel Mayor and Didier Queloz each sharing a quarter for ‘the discovery of an exoplanet orbiting a solar type star’. Peebles In the 1960s, physical cosmology was considered a ‘dead end’ and had very little interest from the community, but Peebles remained committed. His dedication did not fail him: he made significant contributions to the Big Bang Theory, most notably the prediction of the cosmic microwave background radiation (CMBR). When looking at the sky with a radio telescope, a white noise at around a 15 megahertz frequency can be constantly heard. Interestingly enough, this frequency does not change at all no matter the direction you point your telescope, as it is homogeneous and isotropic. This is because of CMBR: the weak but engulfing energy that fills our universe. This radiation is thought to be the relic of the Big Bang, and an attribute to the expanding universe.
