N-Glycosylation on Asn50 of SND1 Is Required for Glioma U87 Cell Proliferation and Metastasis

Figure 4

N-glycosylation of Asn50 induces ER-associated degradation of SND1. (a) U87 cells overexpressing wild-type SND1-EGFP were pretreated with 1 μg/mL TM for 24 h, followed by culture with 10 μM MG132 or 50 μM CQ for 0 h, 1.5 h, and 3 h. The expression level of exogenous SND1 was then determined by immunoblot. (b) U87 cells overexpressing wild-type SND1-EGFP and N50Q-EGFP were treated with MG132 for 3 h before collection of whole lysates. Exogenous expression was then determined by immunoblot. (c) Cells expressing EGFP, SND1-EGFP, and N50Q-EGFP were analyzed by western blot to determine the levels of GRP94, GRP78, CHOP, and CNX. GAPDH was used as a loading control. All these data are representative of at least three independent experiments.

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