In the central nervous system GABA functions as the main inhibitory transmitter by increasing a Cl-conductance that inhibits neuronal firing. GABA has been shown to activate both ionotropic (GABAA) and metabotropic (GABAB) receptors as well as a third class of receptors called GABAC. In addition to GABA receptors, several proteins have been identified as regulators of GABA
function, including GAD65, GAD67, GABA transporters and GABARAP (GABAA receptor-associated protein). GABARAP associates with GABAA Rg2 to link GABAA receptors to the cytoskeleton. The GABARAP protein sequence is similar to light chain-3 of microtubule-associated proteins (MAPs) suggesting that it may be a type of MAP or a component of a MAP complex.