GABA transporter

These transporters are primarily responsible for the regulation of extracellular GABA concentration during basal and synaptic activity.

[1] GABA transporters are a common target for anticonvulsant drugs against seizure disorders such as epilepsy.

The GABA transporter is an active system, electrogenic, a voltage-dependent which relies on the inward electrochemical gradient of Na+ ions instead of ATP.

[5] It also has low micromolecular affinity to GABA with a Michaelis-Menten constant of 2.5 μM,[1] and requires the presence of Cl- ions in the extracellular matrix.

[2] Because of the similarity, the LeuTa protein provides a very close template model for the studying the transporters in greater detail.

[5] GABA creates an inhibitory tone in the cerebral cortex to counterbalance the neuronal excitability.

To help with epilepsy disorder, anticonvulsant drugs are designed which specifically attack the GABA system.

Molecular phylogenetic analysis of the SLC6 neurotransmitter transporter family in Homo sapiens
The cartoon depicts a GABAergic synapse in adult rat brain where GABA is released exocytotically and acts upon specific post-synaptic receptors. The signal is terminated by removal of GABA from the synaptic cleft by transport of GABA back into the nerve terminal by the plasma membrane GABA transporter (GAT) 1.
Secondary structure and surface representation of LeuTAa. Topology of Aquifex aeolicus LeuTAa. The transporter is composed of 12 trans-membrane regions with cytoplasmic N- and C-terminal domains. TM1 and TM6 are oriented antiparallel to one another and have breaks in their helical structure approximately halfway across the membrane bilayer. The transporter has two extracellular β-strands (green arrows), four extracellular and two intracellular helices