Glutamate decarboxylase 2

Glutamate decarboxylase 2 (GAD2) is a cytosolic enzyme that catalyzes the production of GABA, the primary inhibitory neurotransmitter in the central nervous system (UniProt: Q05329). The protein functions in GABAergic neurotransmission and is expressed across neural tissues where inhibitory signaling is required.

GAD2 has been identified as upregulated in Alzheimer's Disease brain tissue. Analysis of human post-mortem AD brain compared to age-matched controls using tandem mass tag proteomics across subcellular fractions revealed increased GAD2 levels, with a mean log2 fold-change of 0.30 (Chaparral AD proteomics). This upregulation was detected in one of the examined subcellular fractions. The biological significance of elevated GAD2 in AD pathology—whether representing a compensatory response to neuronal loss, altered GABAergic circuit dynamics, or a direct consequence of disease processes—remains to be determined.