2019 Nobel prize: physiology
Time for another Nobel Prize explainer. Here's Eva Higginbotham from Cambridge University...
Eva - Oxygen is absolutely essential for human and animal life because our cells use it to convert food into energy. So we’ve evolved a lot of different mechanisms to make sure we have enough oxygen in our blood, starting with just breathing faster when running for the bus or at the gym.
But, our bodies are also excellent at sensing when we’re in a low oxygen environment in general, like up a high mountain, and then adapting in response. The 2019 Nobel Prize in Physiology or Medicine has been awarded to the three scientists that figured out how your cells sense and adapt to environments with different levels of oxygen. Gregg L. Semenza, Sir Peter J. Ratcliffe, and William G. Kaelin Jr each independently figured out different pieces of the puzzle, and it comes down to a few proteins, a few genes, and some oxygen-sensitive enzymes.
These enzymes behave differently in low or high oxygen environments, and act on a protein called hypoxia inducible factor, or HIF, which is produced in our cells. Now, when there’s plenty of oxygen around, HIF is produced but then labelled for rapid degradation by the aforementioned enzymes. But in a low oxygen environment HIF isn’t labeled, and instead gets busy binding to a host of genes that promote adaptive responses, like the gene for the hormone erythropoietin, or EPO, which makes you make more red blood cells.
Oxygen-sensing is a fundamental part of healthy human and animal life, but this work has even influenced drug-development for patients with diseases like chronic renal failure, who often suffer from anemia caused by low erythropoietin expression. It’s also shaped plans for novel cancer treatments, as one of the important steps in cancer development is the tumour stimulating the production of new blood vessels, and that’s controlled by the oxygen-regulated machinery these new Nobel Laureates discovered.
And, for me, as a PhD student in biology, I feel like the process of discovery here is such a nice example of how science works when it’s at its best: each scientist working hard to contribute knowledge to a field in these little segments over the years, adding piece by piece, until the picture of exactly how a process works becomes clear. It’s a story in science that all scientists can aspire to.
So we can all breathe easy knowing that Semenza, Ratcliffe, and Kaelin have been justly rewarded for their breath-taking work.