Fig. 3.

ebs3-1 likely affects assembly of the N-glycan precursor. (A) Immunoblot analysis of BRI1 in WT and ebs3-1 BRI1⁺. (B) Analysis of LLOs in bri1-9, ebs3-1 bri1-9, and a transgenic gEBS4 ebs3-1 bri1-9 line. LLOs of mature plants were extracted, acid-hydrolyzed, fluorescently labeled with PA, and analyzed using SF-HPLC by comparing their elution profiles with that of PA-sugar chain standards (Mn for Man_nGlcNAc₂-PA and G3M9 for Glc₃Man₉GlcNAc₂-PA). Asterisks indicate minor contaminants derived from the labeling process. (C) ebs3-1 affects the electrophoretic mobility of several ER-localized glycoproteins. For A and C, equal amounts of total proteins from 4-wk-old leaves were separated by SDS/PAGE and analyzed by immunoblot with antibodies against BRI1, maize CRT, PDI, or BiP. Numbers on the left indicate molecular mass. Coomassie blue staining of RbcS served as a loading control.