Aptamer biosensors to measure PAR dynamics in living cells

PolyADP-ribosylation (PARylation) is a reversible post-translational modification where poly ADP-ribose (PAR) chains are assembled onto acceptor proteins. PARylation regulates various fundamental cellular processes including chromatin organisation, DNA repair, transcription and replication. PAR chains are synthesised by PAR polymerases (PARPs), and catabolised by PAR glycohydrolases (PARGs); so PAR dynamics is carefully regulated by the balance between both enzyme classes. However, we currently lack the ability to measure PAR dynamics in living cells.
The aim of the project is to explore fluorescent or other chemically modified and measurable aptamers as 'PAR biosensors' capable of binding to PAR chains in living cells; and to generate new tools to study PARylation and its role in DNA damage, repair and replication in normal cellular physiology and pathological states such as ovarian and prostate cancers, with the industrial partner, Aptamer Group. The student will generate synthetic PARylated peptides; create aptamer beacons and evaluate the PAR biosensor(s) in living cells. The student will receive a broad interdisciplinary skills training in state-of-the-art aptamer technology for developing novel biosensors, in vitro analytical techniques and cell biology methods (cell culture, time-lapse and immunofluorescence microscopy), and functional assays (e.g. apoptosis, replication stress). They will also gain a strong intellectual training in the relevant background (cell cycle, DNA replication and cancer), and in experimental design and strategic multidisciplinary approaches.