An inter-subunit disulfide bond of artemin acts as a redox switch for its chaperone-like activity
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Encysted embryos of Artemia are among the most stress-resistant eukaryotes partly due to the massive amount of a cysteine-rich protein termed artemin. High number of cysteine residues in artemin and their intramolecular spatial positions motivated us to investigate the role of the cysteine residues in the chaperone-like activity of artemin. According to the result of Ellman’s assay, there are nine free thiols (seven buried and two exposed) and one disulfide bond per monomer of artemin. Subsequent theoretical analysis of the predicted 3D structure of artemin confirmed the data obtained by the spectroscopic study. Native and reduced/modified forms of artemin were also compared with respect to their efficiency in chaperoning activity, tertiary structure, and stability. Since the alkylation and reduction of artemin diminished its chaperone activity, it appears that its chaperoning potential depends on the formation of intermolecular disulfide bond and the presence of cysteine residues. Comparative fluorescence studies on the structure and stability of the native and reduced protein revealed some differences between them. Due to the redox-dependent functional switching of artemin from the less to more active form, it can be finally suggested as a redox-dependent chaperone.
KeywordsArtemin Cysteine-rich protein Redox-dependent chaperone Disulfide bond
The authors express their gratitude to the research council of Tarbiat Modares University and University of Guilan for financial support during the course of this project.
- Beveridge T, Toma SJ, Nakai S (1974) Determination of SH-and SS-groups in some food proteins using Ellman’s reagent. J Food Sci 39(1):49–51. https://doi.org/10.1111/j.1365-2621.1974.tb00984.x CrossRefGoogle Scholar
- Day RM, Gupta JS, MacRae TH (2003) A small heat shock/α-crystallin protein from encysted Artemia embryos suppresses tubulin denaturation. Cell Stress Chaperones 8(2):183–193. https://doi.org/10.1379/1466-1268(2003)008<0183:ASHCPF>2.0.CO;2 CrossRefPubMedPubMedCentralGoogle Scholar
- Gilbert HF (1993) Molecular and cellular aspects of thiol-disulfide exchange. Adv Enzymol Relat Areas Mol Biol 63:69–172Google Scholar
- Hu Y, Bojikova-Fournier S, King AM, MacRae TH (2011) The structural stability and chaperone activity of artemin, a ferritin homologue from diapause-destined Artemia embryos, depend on different cysteine residues. Cell Stress Chaperones 16(2):133–141. https://doi.org/10.1007/s12192-010-0225-7 CrossRefPubMedGoogle Scholar
- Janda I, Devedjiev Y, Derewenda U, Dauter Z, Bielnicki J, Cooper DR, Graf PC, Joachimiak A, Jakob U, Derewenda ZS (2004) The crystal structure of the reduced, Zn 2+-bound form of the B. subtilis Hsp33 chaperone and its implications for the activation mechanism. Structure 12(10):1901–1907. https://doi.org/10.1016/j.str.2004.08.003 CrossRefPubMedPubMedCentralGoogle Scholar
- Mayer M, Buchner J (2004) Refolding of inclusion body proteins. In: Decker J, Reischl U (eds) Molecular diagnosis of infectious diseases. Humana Press Inc, Totowa, (NJ), pp 239–245Google Scholar
- Mcauley A, Jacob J, Carl GK, Westland K, Lee HJ, Stephen RB, Rehder D, Gerd RK, David NB, Matsumura M (2008) Contributions of a disulfide bond to the structure, stability, and dimerization of human IgG1 antibody CH3 domain. Protein Sci 17:95–106. https://doi.org/10.1110/ps.073134408 CrossRefPubMedPubMedCentralGoogle Scholar
- Zavialov A, Benndorf R, Ehrnsperger M, Zav’yalov V, Dudich I, Buchner J (1998) The effect of the intersubunit disulfide bond on the structural and functional properties of the small heat shock protein Hsp25. Int J Biol Macromol 22(3-4):163–173. https://doi.org/10.1016/S0141-8130(98)00014-2 CrossRefPubMedGoogle Scholar