Helicases and topoisomerases are energy-coupling enzymes that convert the energy of ATP hydrolysis into structural changes in their substrates. RNA helicases mediate a multitude of RNA rearrangements in transcription, splicing, RNA editing, translation, RNA export, ribosome assembly, RNA degradation, and potentially RNA folding in general. In accordance with their variety of functions, they are associated with complex processes such as ageing, differentiation, and cancer. Topoisomerases change the topology of DNA in an ATP-dependent reaction. DNA topology impacts key cellular events such as replication, transcription, recombination, and the storage of the genome as chromatin. Furthermore, cooperation between helicases and topoisomerases is required to maintain genome integrity.
Our lab investigates the role of ATP-driven conformational changes for the catalytic activity of helicases and topoisomerases, using a wide variety of techniques from molecular biology, protein and nucleic acid biochemical techniques, FPLC and HPLC chromatography, absorption, fluorescence and circular dichroism spectroscopy, steady-state and pre-steady-state kinetics, to high-end time-resolved single-molecule fluorescence spectroscopy (confocal and total internal reflection microscopy).