Structural elements required for coupling ion and substrate transport in the neurotransmitter transporter homolog LeuT.

ABSTRACT: The coupled transport of ions and substrates allows transporters to accumulate substrates using the energy of transmembrane ion gradients and electrical potentials. During transport, conformational changes that switch accessibility of substrate and ion binding sites from one side of the membrane to the other must be controlled so as to prevent uncoupled movement of ions or substrates. In the neurotransmitter:sodium symporter (NSS) family, Na⁺ stabilizes the transporter in an outward-open state, thus decreasing the likelihood of uncoupled Na⁺ transport. Substrate binding, in a step essential for coupled transport, must overcome the effect of Na⁺, allowing intracellular substrate and Na⁺ release from an inward-open state. However, the specific elem

SUBMITTER: Zhang YW 

PROVIDER: S-EPMC6156673 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature