Regional expression and dietary regulation of rat small intestinal peptide and amino acid transporter mRNAs.
RT-PCR was used to obtain rat small intestinal cDNAs for two peptide transporters, showing conclusively for the first time that both are present in normal intestinal mucosa. Sequencing of these cDNAs showed them to be highly homologous and similar to two different types of peptide transport proteins from either colorectal carcinoma cells (Caco-2) or human and rabbit intestine. An even distribution profile of steady state levels of mRNA for both peptide transporters was observed along the longitudinal axis of small intestine. Both were upregulated in the distal regions of intestine by a high protein diet. Also, high levels of the rat high affinity glutamate transporter EAAC1 were observed in the distal intestine. These results suggest that the distal regions of small intestine play an important role in the absorption of some amino acids and peptides. Furthermore this area appears to be a primary site where dietary-induced changes in peptide and amino acid transport occurs.
D000595:Amino Acid Sequence; D027322:Amino Acid Transport System X-AG; D026905:Amino Acid Transport Systems; D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002352:Carrier Proteins / Q000096:biosynthesis*; D002460:Cell Line; D015179:Colorectal Neoplasms; D017931:DNA Primers; D004032:Diet; D050580:Excitatory Amino Acid Transporter 3; D015870:Gene Expression; D005786:Gene Expression Regulation; D050491:Glutamate Plasma Membrane Transport Proteins; D018698:Glutamic Acid / Q000378:metabolism; D006801:Humans; D007408:Intestinal Absorption; D007413:Intestinal Mucosa / Q000378:metabolism*; D007421:Intestine, Small / Q000378:metabolism*; D008969:Molecular Sequence Data; D000074011:Peptide Transporter 1; D010455:Peptides / Q000378:metabolism; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D011817:Rabbits; D051381:Rats; D017386:Sequence Homology, Amino Acid; D027981:Symporters; D014407:Tumor Cells, Cultured
D027322:Amino Acid Transport System X-AG; D026905:Amino Acid Transport Systems; D000596:Amino Acids; D002352:Carrier Proteins; D017931:DNA Primers; D050580:Excitatory Amino Acid Transporter 3; D050491:Glutamate Plasma Membrane Transport Proteins; D000074011:Peptide Transporter 1; D010455:Peptides; D012333:RNA, Messenger; C082186:SLC15A1 protein, human; C493400:SLC1A1 protein, human; C489940:Slc15a1 protein, rat; C493398:Slc1a1 protein, rat; D027981:Symporters; D018698:Glutamic Acid