OGA Gene (O-GlcNAcase): Function, Expression, and Disease Associations | Biomedical Reference

The OGA gene encodes O-GlcNAcase, an enzyme that catalyzes the removal of N-acetylglucosamine residues from serine and threonine residues of cytoplasmic and nuclear proteins. This post-translational modification, known as O-GlcNAcylation, is a dynamic and reversible process that regulates numerous cellular processes including signal transduction, transcription, and metabolism. OGA is the counterpart to O-GlcNAc transferase (OGT), which adds the sugar moiety. The balance between OGT and OGA activity is critical for cellular homeostasis, and dysregulation has been implicated in various diseases, including diabetes, cancer, and neurodegenerative disorders.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• O-GlcNAc modification of proteins

• Insulin signaling pathway

• Hexosamine biosynthetic pathway

• Tau protein modification in Alzheimer's disease

O-GlcNAcase (OGA) is a 916-amino acid protein that functions as a glycoside hydrolase, specifically removing O-linked N-acetylglucosamine (O-GlcNAc) from serine and threonine residues of nuclear and cytoplasmic proteins. The protein contains an N-terminal catalytic domain and a C-terminal pseudo-histone acetyltransferase (HAT) domain. OGA forms a homodimer and is predominantly localized in the cytoplasm, with some presence in the nucleus. It plays a crucial role in cellular signaling by opposing the action of OGT, thereby regulating the dynamic cycle of O-GlcNAcylation. This modification is sensitive to nutrient availability and stress, linking OGA activity to metabolic and stress response pathways.