Fig. 1: XBP1s-induction upregulates high mannose N-glycans on and within cells.

a Schematic for dox-inducible XBP1s upregulating high mannose N-glycans. b RT-qPCR for targets of general UPRER and XBP1s. Gene expression is normalized to housekeeping genes GAPDH and HRPT1. c Fluorescent HHL and GRFT binding on A549 cells with or without dox-induction of XBP1s. Cells were treated with 2 µg/mL dox for 48 hours to overexpress XBP1s. d Fluorescent MBL2 binding on A549 cells with or without dox-induction of XBP1s. Cells were treated with 2 µg/mL dox for 48 hours to overexpress XBP1s. e UPLC quantification of high mannose N-glycan structures of A549 cells with or without XBP1s-induction. Levels of each high mannose structure are normalized to the protein amount of each replicate. f Schematic for lectin microarray analysis of A549s under basal or XBP1s-induced conditions. g Volcano plot of lectin microarray data. Median normalized log2 ratios (sample /reference) of the A549 samples are presented. Lectins are color-coded by their glycan-binding specificities. All Data are presented as mean ± s.e.m. unless otherwise indicated, and are representative of at least two independent experiments performed in triplicate with consistent results. p values were calculated from two-tailed Student’s t test.