Protein Thiol Modification and Thiol Proteomics

Cysteine plays an important role in the regulation of redox chemistry and gene expression and is essential in the structural and macromolecular organisation of proteins. Thiol oxidation leads to misfolding and the influencing of the protein function (Buczek et al., 2007). In our experiments, we have identified an oxidised cytoskeletal protein actin involved in the rearrangement of filament in the cells, leading to cellular apoptosis (Wang et al., 2010). Redox signalling can be relayed through intramolecular or intermolecular disulphide formation (Li et al., 2005). Redox proteomics is an emerging branch of proteomics aimed at detecting and analysing redox-based changes within the proteome in different redox statuses (D'Alessandro et al., 2011). For this reason, several experimental approaches have been developed for the systematic characterisation of thiol proteome. One major limit in such an analysis is the chemical labile nature of Cys redox modifications; thus basically two critical steps are needed in analysing the thiol proteome, which consists of a temporary trapping of free thiols and their subsequent reduction (Avellini et al., 2007; Butterfield and Sultana, 2007).