Mutational analysis of calnexin

作者：Groenendyk Jody; Dabrowska Monika; Michalak Marek^*

来源：Biochimica et Biophysica Acta-Biomembranes, 2011, 1808(6): 1435-1440.

DOI：10.1016/j.bbamem.2010.04.001

• Endoplasmic reticulum
• Protein folding
• Calnexin
• Chaperone
• Mutagenesis

Calnexin is a type I endoplasmic reticulum lectin-like chaperone protein. In this study, we have used site-specific mutagenesis to investigate the functional importance of glutamate E(351) found at the tip of the P-domain of calnexin, and tryptophan W(428) found in the carbohydrate binding region of the globular domain of the protein. The E(351) and W(428) calnexin mutants lost the ability to inhibit aggregation of IgY (glycosylated substrate). The E(351) mutation led to slightly enhanced ERp57 binding to calnexin, whereas W(428) greatly enhanced binding of ERp57 to calnexin. These findings indicate that modification of a residue(s) in the carbohydrate binding region may have a profound effect on the structural and functional properties of the P-domain and consequently on association of calnexin with the folding enzyme ERp57.

• 出版日期2011-6