Fig 1: ALG3 enhances radioresistance via regulation of TGFBR2 glycosylation. (a) Downshift of TGFBR2 bands in ALG3-sg cells was detected by Western blot. But not TGFBR1 bands (b) Representative immunofluorescence images of TGFBR2 expression level in cytoplasmic and membrane fractions. (c) A schematic model of different subtypes of N-glycans. The round spots are mannose, the square ones are acetylglucosamine, and the red spot is the initial of the N-glycosylation site, which is initiated by ALG3. (d) TGFBR2 band shift could be seen in ALG3-sg cells or cells treated by tunicamycin. And downregulation of ALG3 reduced the expression level of p-SMAD2. (e) Representative immunofluorescence images of p-SMAD2 expression level in cytoplasmic and nuclear fractions. Nuclear translocation of p-SMAD2 was significantly decreased in ALG3-sg and tunicamycin treatment groups. (f) The co-immunoprecipitation between TGFBR1 and TGFBR2, TGFBR1 and p-SMAD2 could be detected in ALG3-control group, but not tunicamycin treatment, and ALG3-sg groups. (g) TGFBR2 inhibitor (LY2109761) in ALG3-transduced cells decreased the surviving fraction of breast cancer cells after radiation treatment, which were detected by CCK-8 assays. Data were analyzed by two-way ANOVA. Each bar represents the mean ± SD of three independent experiments. (h) Inhibition of TGFBR2 in ALG3-transduced cells decreased the number of colonies after radiation treatment. (i) Inhibition of TGFBR2 in ALG3-transduced cells decreased the proportion of CD44+CD24- cells, which were detected by flow cytometry. “ns” no significance, *P < 0.05