Abstract
O-GlcNAcylation is an essential protein modification catalyzed by O-GlcNAc transferase (OGT). Missense variants in OGT are linked to a novel intellectual disability syndrome known as OGT congenital disorder of glycosylation (OGT-CDG). The mechanisms by which OGT missense variants lead to this heterogeneous syndrome are not understood, and no unified method exists for dissecting pathogenic from non-pathogenic variants. Here, we develop a double-fluorescence strategy in mouse embryonic stem cells to measure disruption of O-GlcNAc homeostasis by quantifying the effects of variants on endogenous OGT expression. OGT-CDG variants generally elicited a lower feedback response than wild-type and Genome Aggregation Database (gnomAD) OGT variants. This approach was then used to dissect new putative OGT-CDG variants from pathogenic background variants in other disease-associated genes. Our work enables the prediction of pathogenicity for rapidly emerging de novo OGT-CDG variants and points to reduced disruption of O-GlcNAc homeostasis as a common mechanism underpinning OGT-CDG.
| Original language | English |
|---|---|
| Article number | 102380 |
| Journal | Stem Cell Reports |
| Volume | 20 |
| Issue | 1 |
| Pages (from-to) | 102380 |
| ISSN | 2213-6711 |
| DOIs | |
| Publication status | Published - 14 Jan 2025 |
Keywords
- Acetylglucosamine/metabolism
- Animals
- Congenital Disorders of Glycosylation/genetics
- Glycosylation
- Homeostasis
- Humans
- Intellectual Disability/genetics
- Mice
- Mouse Embryonic Stem Cells/metabolism
- Mutation, Missense
- N-Acetylglucosaminyltransferases/metabolism
- O-GlcNAc
- neurodevelopment
- OGT-CDG
- OGT