Journal: The Journal of Biological Chemistry
Article Title: Map of the neuronal O-glycoproteome reveals driver functions in the regulated secretory pathway
doi: 10.1016/j.jbc.2025.110313
Figure Lengend Snippet: Probing roles of elaborate O-glycans for regulated secre tion . A , targeting C1GALT1 enzyme or its obligate private COSMC chaperone by CRISPR-Cas9 results in SC cells producing truncated (Tn) O-glycans on proteins. B , representative immunofluorescence images of STC-1 and SH-SY5Y WT and SC cells. Pretreatment with neuraminidase shows the gain of Tn (VVA) and loss of Core 1 (PNA) in SCs and validates the glycoengineering. C and D , Western blot analysis of secretomes ± depolarization from SH-SY5Y and STC-1 WT and SC cells. Blots were pretreated with neuraminidase and probed with the VVA lectin to selectively identify O-glycoproteins with truncated Tn O-glycans. Arrows indicate relative migration of highly glycosylated granins (deferred from separate western blots (Sfig 2C)). A VVA-reactive smear that co-mobilizes with both chondroitin sulfate and high molecular weight CHGA is indicated by a grey arrow . Asterisks (∗) denote background bands. E , Bar plot showing the mean relative secretion of the KCl-responsive proteins in SH-SY5Y WT and ΔCOSMC (SH-SY5Y SC ). Error bars represent + standard error of the mean, n = 5 clones.
Article Snippet: Subsequently, blots were incubated O/N using the following lectins or antibodies: VVA-Biotin 1:2000 (Vector-labs, B-1235–2), PNA-Biotin 1:2000 (Vector-labs, B-1075–5), Anti-CHGA 1:1000 (AbCam, Ab15160), Anti-CS 1:1000 (Abcam, ab11570), Anti-B-actin 1:10.000 (Protein Tech, 66009-1-Ig), anti-CHGB (Abcam, ab12242) or anti-VGF (Abcam, ab69989).
Techniques: CRISPR, Immunofluorescence, Western Blot, Migration, High Molecular Weight, Clone Assay