Proteome changes and DNA damage caused by photoinduced oxidative stress in cells

Abstract

Solar UV radiation is composed of 95% UVA and 5% UVB light. It is still a matter of debate whether or not UVA light plays a role in carcinogenesis and photoaging of exposed skin. UVA light may be absorbed by cellular chromophores, giving rise to photoexcited species, such as singlet oxygen. These species are known mediators of oxidative stress. In this work, we aim to understand how the UVA component of UV radiation is associated with Skin Cancer and photoaging. Proteomic studies applied to photochemistry and photobiology are scarce. Therefore, we will use a type II photosensitizer incorporated into DNA - thioguanine - to analyze proteome alterations caused in cells exposed to UVA light. Proteome analysis will include differences in protein expression, protein-protein and protein-DNA crosslinks and post-translational modifications. Besides, we will also focus on oxidative damages caused by singlet oxygen on DNA. To this end, we will use state-of-the-art technologies, such as a new generation Orbitrap Fusion Lumos mass spectrometer and a confocal fluorescence microscope, which will allows us to localize intracellular production of 1O2. (AU)