Do Amino Acid Antiporters Have Asymmetric Substrate Specificity?

ABSTRACT: Amino acid antiporters mediate the 1:1 exchange of groups of amino acids. Whether substrate specificity can be different for the inward and outward facing conformation has not been investigated systematically, although examples of asymmetric transport have been reported. Here we used LC-MS to detect the movement of ¹²C- and ¹³C-labelled amino acid mixtures across the plasma membrane of Xenopus laevis oocytes expressing a variety of amino acid antiporters. Differences of substrate specificity between transporter paralogs were readily observed using this method. Our results suggest that antiporters are largely symmetric, equalizing the pools of their substrate amino acids. Exceptions are the antiporters y⁺LAT1 and y⁺LAT2 where neutral amino

SUBMITTER: Gauthier-Coles G 

PROVIDER: S-EPMC9953452 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature