CLONING BRAIN LOCALIZATION OF MOUSE GLUTAMYLCYSTEINE SYNTHETASE HEAVY-CHAIN MESSENGER-RNA/

GLUTATHIONE (GSH) is considered the primary molecule responsible for p eroxide removal from the brain. Inhibition of its rate-limiting synthe tic enzyme, glutamylcysteine synthetase (GCS), results in morphologica l damage to both cortical and nigral neurons in rodents. Here, we repo rt cloning of the catalytic heavy chain GCS mRNA from mouse and its lo calization in the murine brain. Heavy chain GCS appears to be localize d in glial populations in the hippocampus, cerebellum and olfactory bu lb, with lower levels of expression in the cortex and substantia nigra . Variations in GCS levels and subsequent GSH synthesis may explain di fferences in susceptibility to neuropathology associated with oxidativ e stress noted in these various brain regions.