Vesicular GABA transporter (VGAT) transports β-alanine

Authors

  • Narinobu Juge,

    Corresponding author
    1. Advanced Research Center, Okayama University, Okayama, Japan
    • Address correspondence and reprint requests to Narinobu Juge, Advanced Research Center, Okayama University, Okayama 700-8530, Japan. E-mail: n-juge@pharm.okayama-u.ac.jp

    Search for more papers by this author
  • Hiroshi Omote,

    1. Department of Membrane Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
    Search for more papers by this author
  • Yoshinori Moriyama

    1. Advanced Research Center, Okayama University, Okayama, Japan
    2. Department of Membrane Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
    Search for more papers by this author

Abstract

Vesicular GABA transporter (VGAT) is expressed in GABAergic and glycinergic neurons, and is responsible for vesicular storage and subsequent exocytosis of these inhibitory amino acids. In this study, we show that VGAT recognizes β-alanine as a substrate. Proteoliposomes containing purified VGAT transport β-alanine using Δψ but not ΔpH as a driving force. The Δψ-driven β-alanine uptake requires Cl. VGAT also facilitates Cl uptake in the presence of β-alanine. A previously described VGAT mutant (Glu213Ala) that disrupts GABA and glycine transport similarly abrogates β-alanine uptake. These findings indicated that VGAT transports β-alanine through a mechanism similar to those for GABA and glycine, and functions as a vesicular β-alanine transporter.

image

Vesicular GABA transporter (VGAT) is expressed in GABAergic and glycinergic neurons, and is responsible for vesicular storage and subsequent exocytosis of these inhibitory amino acids. In the present study, we showed that proteoliposomes containing purified VGAT transport β-alanine using Δψ as a driving force. VGAT also facilitates Cl uptake. Our findings indicated that VGAT functions as a vesicular β-alanine transporter.

Ancillary