mitoDNA Single molecule characterization of the coordinated protein activity dynamics at the human mitochondrial DNA replisome

Dr. Borja Ibarra

Funding : MINECO BFU2015-63714-R

Duration: 2016 - 2019

36 months

Mitochondria are suppliers of energy and building materials as needed by the cell and play a crucial role regulating cellular activity. Malfunction of the proteins involved in the replication of the hmtDNA promotes the onset of chronic, devastating ‘mitochondrial diseases’ and even cancer and premature aging. Using optical tweezers, we have recently proved the possibility to follow in real time the individual activity of each protein constituent of the mitochondrial replisome.

However, these proteins do not work in isolation; their activity is highly coordinated and one protein component is regulated by that of the others. The overall goal of our current proposal is to exploit the properties of optical tweezers, to characterize the molecular basis of the dynamical and mechano-chemical processes that govern the coordinate action of the minimal protein machinery required to faithfully replicate the human mitochondrial genome. In addition, we propose to construct a new optical tweezers device with a temperature controller and use this new technology to perform in singulo thermo-mechanical studies on the mitochondrial replisome. This proposal represents a truly novel approach to determine the mechanistic and  dynamical processes governing the operation of the hmtDNA replication machinery at the molecular level and could ultimately provide  insight into alternative treatment options for human patients with hmtDNA replication-related diseases.