Cal Poly Pomona
Cal Poly Pomona
GABA Transporter Page
Ion-Coupled Cotransport
For some information about the GABA transporters, please see the links provided below:

  • GATMD: GABA Transporter Mutagenesis Database
  • GABA Transporter Stoichiometry and Reversal Potential Calculator

  • Below is a simple cartoon of the transport cycle for the GABA transporters (forward mode). The 3 Na+ : 1 Cl : 1 GABA coupling stoichiometry is supported by a recent study published by this lab (Willford et al., 2015). There is good evidence that, from the extracellular space, two Na+ ions can bind to the transporter even in the absence of GABA. There is also good evidence for GABA binding to the transporter as the last co-substrate before the fully loaded carrier undergoes a conformational change to expose the binding sites to the cytoplasmic domain. At the moment, the order of binding for the Cl ion or the third Na+ ion is not known, and is only speculated in this cartoon.