Fig. 3: Overstimulation of NMDA receptors due to GLDC downregulation and glycine accumulation.
From: Further evidence supporting the role of GTDC1 in glycine metabolism and neurodevelopmental disorders
In the mitochondrial glycine cleavage system (GCS), composed of four enzymes (encoded by GCSH, GLDC, AMT, and DLD) glycine decarboxylase/GLDC converts glycine into CO2 and NH3. The reduced GLDC expression observed in the proband’s LCL may be reflected in the accumulation of unmetabolised glycine in the cytosol of pre-synaptic neurons, leading to increased release of glycine in the synaptic space and overstimulation the NMDA receptors on the surface of post-synaptic neurons. The figure was created with BioRender (https://www.biorender.com/).
