Investigating the role of CLIC1s activation mechanism

CLICs are a family of metamorphic proteins that can exist in both soluble and membrane-bound proteins and function as chloride channels within cells. Their precise activation mechanism is still unknown and poorly understood. Previous studies have suggested that conformational changes within CLIC1 drives insertion with SAXs (Small angle X ray Scattering) were performed to directly compare the behaviour of the C-terminal tagged CLIC1 in the presence of increasing concentrations of Zn2+ to WTCLIC1. This analysis showed differences in membrane insertion, spectra, chemical shift perturbations (CSPs) and intensities further confirming the role the C terminal tag plays in membrane insertion. In addition, CLIC1 is predicted to become phosphorylated at specific serine/threonine residues. To investigate this, in vitro kinase assays were performed and analysed by Western Blot to determine if phosphorylation occurred. NMR experiments were also performed to supplement this assay. The results show that the selected kinases within the study do not phosphorylate wild-type CLIC1at its predicted phosphorylated residues.

More work will need to be done, to further assess and confirm whether phosphorylation does play a role in CLICs activation.