Tracking of in vivo O-GlcNAcylation in an Alzheimer’s Disease and Aging C. elegans Model

We investigated O-linked β-N-acetylglucosamine (O-GlcNAc), a post-translational modification, in an in vivo Caenorhabditis elegans model of Alzheimer’s Disease and aging. Employing a chemoenzymatic labeling strategy combined with an automated image processing, we analyzed both post-hatching and adult stages of wild-type N2 and transgenic strain expressing human tau V337M under the aex -3 promoter ( aex-3p ::tau(V337M)). Labeled O-GlcNAc proteins were visualized via fluorescence microscopy and quantified using a region-of-interest (ROI)-based image analysis pipeline. Morphometric characterization revealed an age-dependent increase in O-GlcNAcylation in wild-type worms, whereas the AD model showed a progressive decline. O-GlcNAc-labeled ROIs exhibited a shift from anterograde to predominantly retrograde transport in middle-aged transgenic nematodes, suggesting that aging and neurodegeneration alter O-GlcNAc trafficking dynamics, potentially reflecting impaired synaptic support or enhanced clearance in C. elegans. Summary statement This study uses a combination of chemoenzymatic labeling and an image processing pipeline to study O-linked N-acetyl glucosamine (post-translational modification)