Cloning Two PepT1 cDNA Fragments of Common Carp, <I>Cyprinus Carpio</I> (Actinopterygii: Cypriniformes: Cyprinidae)

Abstract

Background. Common carp, Cyprinus carpio, is a model organism within Teleostei. Oligopeptides are a new and promising alternative source of amino acids in animal as well as in human nutrition. In common carp, the membrane protein that transports oligopeptides across the enterocyte membrane is encoded by the gene PepT1 (SLC15A1). The aim of this paper was to sequence the PepT1 (SLC15A1) in common carp. Materials and Methods. Intestine samples were isolated from six-week old common carp. Total RNA was isolated using a Trizol method. Reverse transcription was used to synthesize cDNA. Two different pairs of primers were designed, according to the zebrafish (Danio rerio) PepT1 sequence, and used for PCR. The amplified DNA was isolated by electrophoresis, cloned (pCRII-TOPO vectors), sequenced, and subjected to in silico analysis. Results. Two nucleotide fragments of the PepT1 gene were obtained and analyzed using bioinformatic tools. Both fragments showed a high degree of homology with the known PepT1 genes of other teleosts, mammals, and birds. High homology of the PepT1 gene, and similar primary protein structure among the aforementioned taxa probably reflects the conservative function of the PepT1 protein product. Both fragments of the PepT1 gene were deposited in GenBank (FJ556590; FJ529670). Conclusions. The sequenced fragments of the common carp PepT1 gene will allow evaluation of PepT1 expression in the intestines of fish fed diets containing various forms of protein, which is an issue of importance regarding fish nutrition and its import for aquaculture.

The effect of ultrafiltered fish protein hydrolysate level on growth performance, protein digestibility and mRNA expression of PepT1 in juvenile turbot (Scophthalmus maximusL.)

“…Several studies suggested that regulated PepT1 expression by dietary‐free amino acid, peptides and intact protein in fish could affect growth performance directly and/or indirectly (Ostaszewska et al . , ,b; Bakke et al . ; Liu et al .…”

Intestinal B0AT1 (SLC6A19) and PEPT1 (SLC15A1) mRNA levels in European sea bass (Dicentrarchus labrax) reared in fresh water and fed fish and plant protein sources

“…The PEPT1 gene has been characterised in many vertebrates, including fish, such as zebrafish ( Danio rerio ) ( 27 ) , sea bass ( Dicentrarchus labrax ) ( 28 ) , common carp ( Cyprinus carpio ) ( 29 ) , Atlantic salmon ( Salmo salar ) ( 30 ) , rainbow trout ( Onchorhynchus mykiss ) ( 31 ) , yellow perch ( Perca flavescens ) ( 32 ) and sea bream ( Sparus aurata ) ( 33 ) . According to these studies, the PEPT1 gene is specifically expressed in the intestinal tract and its transcript levels are related to fish nutritional status, which is down-regulated during fasting and up-regulated during refeeding ( 28 ) .…”

Tilapia protein hydrolyzate improves growth performance, protein absorption and antioxidant status in Silver catfish ( Rhamdia quelen )

“…Peptides have a faster absorption pathway in the intestine through the hydrogen/peptide symmetry in the PEPT 1, which decreases competition with other nutrients at uptake sites of enterocytes (Daniel, ). Upon entering the enterocyte, the peptides are cleaved by endogenous peptidases to form amino acids, which are then transported to the liver via the bloodstream for subsequent metabolism (Ostaszewska et al, ; Romano, Barca, Storelli, & Verri, ). The relationship between PEPT and the presence of di and tripeptides was shown for juveniles of Atlantic Cod ( G. morhua ; Bakke et al, ).…”