title: New mechanisms that regulate Saccharomyces cerevisiae short peptide transporter achieve balanced intracellular amino acid concentrations.
abstract: The budding yeast Saccharomyces cerevisiae is able to take up large quantities of amino acids in the form of di- and tripeptides via a short peptide transporter, Ptr2p. It is known that PTR2 can be induced by certain peptides and amino acids, and the mechanisms governing this upregulation are understood at the molecular level. We describe two new opposing mechanisms of regulation that emphasize potential toxicity of amino acids: the first is upregulation of PTR2 in a population of cells, caused by amino acid secretion that accompanies peptide uptake; the second is loss of Ptr2p activity, due to transporter internalization following peptide uptake. Our findings emphasize the importance of proper amino acid balance in the cell and extend understanding of peptide import regulation in yeast.
authors.affiliation: Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Artem V
authors.identifier: http://orcid.org/0000-0002-4733-4249
authors.initials: AV
authors.lastname: Melnykov
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000378:metabolism*; D061249:Batch Cell Culture Techniques / Q000379:methods; D001692:Biological Transport; D003593:Cytoplasm / Q000378:metabolism; D005434:Flow Cytometry; D015966:Gene Expression Regulation, Fungal; D026901:Membrane Transport Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D010455:Peptides / Q000378:metabolism*; D021381:Protein Transport; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D000596:Amino Acids; D026901:Membrane Transport Proteins; C093495:PTR2 protein, S cerevisiae; D010455:Peptides; D029701:Saccharomyces cerevisiae Proteins; C043912:peptide permease
keywords: amino acid excretion; amino acid toxicity; peptide transport