The C-terminal domain (residues 518-803) of the 94 kDa glucose regulated protein (grp94) was expressed in Escherichia coli as a fusion protein with a His6-N-terminal tag (grp94-CT). This truncated form of grp94 formed dimers and oligomers that could be dissociated into monomers by treatment with dithiothreitol. Grp94-CT conferred protection against aggregation on the catalytic subunit of protein kinase CK2 (CK2α), although it did not protect against thermal inactivation. This anti-aggregation effect of grp94-CT was concentration dependent, with full protection achieved at grp94-CT/CK2α molar ratios of 4 : 1. The presence of dithiothreitol markedly reduced the anti-aggregation effects of grp94-CT on CK2α without altering the solubility of the chaperone. It is concluded that the chaperone activity of the C-terminal domain of human grp94 requires the maintenance of its quaternary structure (dimers and oligomers), which seems to be stabilised by disulphide bonds.
|Journal||European Journal of Biochemistry|
|Publication status||Published - 1 Jan 2001|
- Chaperone assay
- Protein kinase CK2
Roher, N., Miró, F., Boldyreff, B., Llorens, F., Plana, M., Issinger, O. G., & Itarte, E. (2001). The C-terminal domain of human grp94 protects the catalytic subunit of protein kinase CK2 (CK2α) against thermal aggregation: Role of disulfide bonds. European Journal of Biochemistry, 268, 429-436. https://doi.org/10.1046/j.1432-1033.2001.01905.x