Plants for Space Seminar: Dr Kate Poole

Associate Professor Kate Poole, UNSW’s School of Biomedical Sciences

Mechanosensitive ion channels regulate the impact of microgravity on mammalian cells.

Abstract: Life on Earth has evolved under the constant impact of Earth’s gravity, defined as 1g. Some organisms, including plants and some ciliates, perceive and respond to the direction of the gravitational vector. However, individual cells from organisms that do not exhibit gravitropic behaviour can still exhibit changes in both form and function under conditions of microgravity. The molecular mechanisms that underpin such changes are not well understood. To extend the capacity for human habitation in low gravity environments, these molecular mechanistic underpinnings need to be better understood in order to design mitigation strategies to preserve human performance. We hypothesise that mechanosensitive ion channels also regulate cellular adaptations to conditions of simulated microgravity in cells that lack specific gravity sensing structures. We have used ground-based studies to simulate microgravity, using a random positioning machine. Starting with human cancer cells as a model, we found that simulated microgravity resulted in cellular detachment and alterations in cellular structure, changes in focal adhesion structures and alterations in the localisation of the YAP1 transcription factor. In cell lines lacking ELKIN1, a mechanosensitive ion channel, the microgravity driven changes noted in wild type cells were ablated. These data indicate a role for mechanosensitive ion channels in cellular adaptations to microgravity, however the complexity of the human cancer cells, their variant morphology and the isolation of these individual cells from their native environment hamper further investigation using this system. We are establishing new model systems to investigate the mechanisms by which microgravity disrupts cellular function, by studying non-adherent cells with simple morphologies to further expand our understanding of the molecular underpinnings of cellular adaptations to microgravity.

Bio: Dr Kate Poole is an Associate Professor at UNSW’s School of Biomedical Sciences. She received her PhD from the University of Adelaide (2002) and completed post-doctoral training in Germany: at Max Planck Institute for Molecular Cell Biology, Dresden, and Max Delbrück Center for Molecular Medicine, Berlin. In between, Kate spent a couple of years working in industry for the Atomic Force Microscopy company, JPK Instruments, AG. She established her own research group in 2012 at the Max Delbrück Center in Berlin supported by a Cecile Vogt Fellowship and returned to Australia in 2016 when she was recruited as a group leader in Single Molecule Science at UNSW. She currently leads the Cellular Mechanotransduction laboratory and acts as Director of Research for the School of Biomedical Sciences. Her research seeks to understand how cells sense and respond to their mechanical environment, with a focus on identifying and characterising the molecular force sensors that convert mechanical information into biological signals.