The Orphan Transporter Rxt1/NTT4 (SLC6A17) Functions as a Synaptic Vesicle Amino Acid Transporter Selective for Proline, Glycine, Leucine, and Alanine

  title={The Orphan Transporter Rxt1/NTT4 (SLC6A17) Functions as a Synaptic Vesicle Amino Acid Transporter Selective for Proline, Glycine, Leucine, and Alanine},
  author={Leonardo A Parra and Tracy B. Baust and Salah El Mestikawy and Marisol E. Quiroz and Beth I. Hoffman and Jack M Haflett and Jeffrey K. Yao and Gonzalo E. Torres},
  journal={Molecular Pharmacology},
  pages={1521 - 1532}
Rxt1/NTT4 (SLC6A17) belongs to a gene family of “orphan transporters” whose substrates and consequently functions remain unidentified. Although Rxt1/NTT4 was previously thought to function as a sodium-dependent plasma membrane transporter, recent studies localized the protein to synaptic vesicles of glutamatergic and GABAergic neurons. Here, we provide evidence indicating that Rxt1/NTT4 functions as a vesicular transporter selective for proline, glycine, leucine, and alanine. Using Western blot… 

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