The role of N-glycosylation in transport function and surface targeting of the human solute carrier PAT1

FEBS Lett. 2009 May 19;583(10):1631-6. doi: 10.1016/j.febslet.2009.04.037. Epub 2009 May 3.


In the present study we show in the Xenopus laevis expression system that the proton-coupled amino acid transporter 1 (PAT1, SLC36A1) is glycosylated at asparagine residues N174, N183 and N470. To determine the functional role of N-glycosylation, glycosylation-deficient mutants were analyzed by two-electrode voltage-clamp measurements after expression in X. laevis oocytes. Single replacements of asparagine residues had no effect on transport activity. However, multiple substitutions resulted in a decreased transport rate, leaving K(t) unchanged. Immunofluorescence localisation revealed a diminished plasma membrane expression of glycosylation-defective mutants. This indicates that N-glycans are not required for transport function, but are important for membrane targeting.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Transport Systems / metabolism*
  • Animals
  • Fluorescent Antibody Technique
  • Glycosylation
  • Humans
  • Models, Biological
  • Mutagenesis, Site-Directed
  • Oocytes / metabolism
  • Patch-Clamp Techniques
  • Protein Transport / physiology
  • Symporters / metabolism*


  • Amino Acid Transport Systems
  • SLC36A1 protein, human
  • Symporters