Molecular and functional characterisation of the zebrafish (Danio rerio) PEPT1-type peptide transporter.
We report the molecular and functional characterisation of a novel peptide transporter from zebrafish, orthologue to mammalian and avian PEPT1. Zebrafish PEPT1 is a low-affinity/high-capacity system. However, in contrast to higher vertebrate counterparts in which maximal transport activity is independent of extracellular pH, zebrafish PEPT1 maximal transport rates unexpectedly increase at alkaline extracellular pH. Zebrafish pept1 is highly expressed in the proximal intestine since day 4 post-fertilisation, thus preceding functional maturation of the gut, first feeding and complete yolk resorption. Zebrafish PEPT1 might help to understand the evolutionary and functional relationships among vertebrate peptide transporters. Moreover, zebrafish pept1 can be a useful marker for screening mutations that affect gut regionalisation, differentiation and morphogenesis.
Verri
Tiziano
T
Department of Biological and Environmental Sciences and Technologies, University of Lecce, via Provinciale Lecce-Monteroni, I-73100 Lecce, Italy. physiol@ultra5.unile.it
Kottra
Gabor
G
Romano
Alessandro
A
Tiso
Natascia
N
Peric
Mark
M
Maffia
Michele
M
Boll
Michael
M
Argenton
Francesco
F
Daniel
Hannelore
H
Storelli
Carlo
C
D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D004594:Electrophysiology; D005314:Embryonic and Fetal Development; D006863:Hydrogen-Ion Concentration; D007413:Intestinal Mucosa / Q000378:metabolism; D007700:Kinetics; D008969:Molecular Sequence Data; D009865:Oocytes; D000074011:Peptide Transporter 1; D010802:Phylogeny; D027981:Symporters; D014018:Tissue Distribution; D014981:Xenopus; D015027:Zebrafish / Q000196:embryology / Q000235:genetics*; D029961:Zebrafish Proteins
D002352:Carrier Proteins; D000074011:Peptide Transporter 1; D027981:Symporters; D029961:Zebrafish Proteins; C000613207:slc15a1b protein, zebrafish