Reglucosylation glycoproteins

Trombetta, E. S., and Helenius, A. (1999). Glycoprotein reglucosylation and nucleotide sugar utilization in the secretory pathway Identification of a nucleoside diphosphatase in the endoplasmic reticulum. EMBO J. 18, 3282-3292. 

Fig. 4. A model for the involvement of calnexin in quality control mechanism in ER. Association and disengagement of calnexin depend on the folding status of the semiprocessed glycoprotein. Calnexin recognizes partially trimmed monoglucosylated glycans, generated either by glucose trimming or by reglucosylation pathways. Symbols and abbreviations are same as Fig. 3 (adopted from [45])...

As several glycoproteins were tested as substrates for GT in vitro, it was noticed that none was an acceptor in its native state, even when the oligosaccharides were highly exposed, while all had to be denatured to be reglucosylated (27). These observations raised the radical notion that glycoproteins had to be devoid of a native conformation to be recognized as substrates by GT. Based on this unique property, it was suggested that... 

The selective association of CNX/CRT with incompletely assembled glycoproteins and the close correlation of such interactions with their residence in the ER indicated that the lectins participated in the retention of incompletely folded glycoproteins (117). Together with the selective reglucosylation of incompletely folded glycoproteins, these... 

Parodi, A. J., Reglucosylation of glycoproteins and quality control of glycoprotein folding in the endoplasmic reticulum of yeast cells, Biochim. Biophys. Acta, 1999, 1426, 287-295. 

Hebert, D.N., Foellmer, B., Helenius, A. Glucose Trimming and Reglucosylation Determine Glycoprotein Association with Calnexin in the Endoplasmic Reticulum Cell 1995 81, 425-433. 

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