Abstract
IN mammals, active transport of organic solutes across plasma membranes was thought to be primarily driven by the Na+ gradient1-3. Here we report the cloning and functional characterization of a H +-coupled transporter of oligopeptides and peptide-derived antibiotics from rabbit small intestine. This new protein, named PepT1, displays an unusually broad substrate specificity. PepT1-mediated uptake is electrogenic, independent of extracellular Na+, K+ and Cl-, and of membrane potential. PepT1 messenger RNA was found in intestine, kidney and liver and in small amounts in brain. In the intestine, the PepTl pathway constitutes a major mechanism for absorption of the products of protein digestion. To our knowledge, the PepT1 primary structure is the first reported for a proton-coupled organic solute transporter in vertebrates and represents an interesting evolutionary link between prokaryotic H +-coupled and vertebrate Na+-coupled transporters of organic solutes.
Original language | English (US) |
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Pages (from-to) | 563-566 |
Number of pages | 4 |
Journal | Nature |
Volume | 368 |
Issue number | 6471 |
DOIs | |
State | Published - 1994 |
ASJC Scopus subject areas
- General