BMC Seminar Thursday 5 December, 12:00 in Læknagarður, Vatnsmýrarvegur 16, room 343
Title: Illuminating the dark proteome, one molecule at a time
Speaker: Dr. Pétur Orri Heiðarsson, Associate Professor at the Faculty of Physical Sciences, University of Iceland
Abstract: About a third of the human proteome is predicted to consist of proteins that lack a well-defined three-dimensional structure under physiological conditions. These so-called intrinsically disordered proteins (IDPs) defy the structure-function paradigm by remaining functional while fluctuating in an ensemble of conformational states. Biomolecular processes involving disordered interactions lie outside the scope of current structural proteomics and thus our understanding of this dark proteome has remained limited. Single-molecule spectroscopy in combination with Förster resonance energy transfer (FRET) is a powerful technique to study both ordered and disordered proteins. The method enables a quantitative measure of molecular distance distributions and dynamics from picoseconds to hours, one molecule at a time. By resolving individual molecules we can go beyond the ensemble average, observe transient or rare events, and explore in detail complex molecular mechanisms involving IDPs.
In this talk I will first discuss the peculiar properties of IDPs and how we use single-molecule spectroscopy to study their structure and dynamics. Then I will present our recent work on highly disordered proteins which has uncovered novel interaction modes and a remarkable regulatory mechanism involved in chromatin condensation.
Bio: I received my B.Sc. and M.Sc. degrees in biochemistry at the University of Iceland, where I studied the link between enzyme kinetics and flexibility. In 2008 I joined the Structural Biology and NMR Laboratory for Ph.D studies where I used nuclear magnetic resonance spectroscopy and single-molecule optical tweezers to study the protein folding problem. Subsequently, I received a postdoctoral fellowship from the Lundbeck Foundation, and later an EMBO short-term grant, to study misfolding and chaperone action in a joint project with Professor Jane Clarke at the University of Cambridge, Professor Birthe Kragelund at the University of Copenhagen, and Professor Ciro Cecconi at the University of Modena and Reggio Emilia. Finally, I received postdoctoral fellowships from the Novo Nordisk Foundation and the Carlsberg Foundation to study intrinsically disordered protein complexes with single-molecule spectroscopy, at the lab of Professor Ben Schuler, University of Zurich. In 2019, I joined the Department of Biochemistry, University of Iceland, as Associate Professor.