Biomaterial Database

Expression of rat intestinal L-lysine transport systems in isolated oocytes of Xenopus laevis. 1993

C M Harvey, and W R Muzyka, and S Y Yao, and C I Cheeseman, and J D Young

Department of Physiology, Faculty of Medicine, University of Alberta, Edmonton, Canada.

The mechanisms by which cationic amino acids are transported across the intestinal epithelium are poorly understood. We show that isolated stage VI oocytes of Xenopus laevis can express lysine transport activity, which is due to the microinjection of mRNA from rat small intestine. L-Lysine transport activity (0.2 mM, 20 degrees C) reaches 400 pmol.oocyte-1.h-1, compared with a typical endogenous rate of 85 pmol.oocyte-1.h-1. Na(+)-dependence and amino acid inhibition studies resolved the expressed transport activity into three components: 1) a Na(+)-dependent transport system that can be inhibited by leucine with high affinity and also by alanine; 2) a Na(+)-independent system that can be inhibited by leucine with high affinity when Na+ is present, but this affinity is reduced in its absence; 3) a Na(+)-independent system that is inhibited by leucine with high affinity only when Na+ is present. Peak arginine-inhibitable lysine influx was found in a mRNA size fraction of 1.5-2.25 (median 2.0) kb.

UI	MeSH Term	Description	Entries
D007267	Injections	Introduction of substances into the body using a needle and syringe.	Injectables,Injectable,Injection
D007413	Intestinal Mucosa	Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI.	Intestinal Epithelium,Intestinal Glands,Epithelium, Intestinal,Gland, Intestinal,Glands, Intestinal,Intestinal Gland,Mucosa, Intestinal
D007930	Leucine	An essential branched-chain amino acid important for hemoglobin formation.	L-Leucine,Leucine, L-Isomer,L-Isomer Leucine,Leucine, L Isomer
D008239	Lysine	An essential amino acid. It is often added to animal feed.	Enisyl,L-Lysine,Lysine Acetate,Lysine Hydrochloride,Acetate, Lysine,L Lysine
D009865	Oocytes	Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).	Ovocytes,Oocyte,Ovocyte
D011061	Poly A	A group of adenine ribonucleotides in which the phosphate residues of each adenine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.	Adenine Polynucleotides,Polyadenylic Acids,Poly(rA),Polynucleotides, Adenine
D002469	Cell Separation	Techniques for separating distinct populations of cells.	Cell Isolation,Cell Segregation,Isolation, Cell,Cell Isolations,Cell Segregations,Cell Separations,Isolations, Cell,Segregation, Cell,Segregations, Cell,Separation, Cell,Separations, Cell
D000409	Alanine	A non-essential amino acid that occurs in high levels in its free state in plasma. It is produced from pyruvate by transamination. It is involved in sugar and acid metabolism, increases IMMUNITY, and provides energy for muscle tissue, BRAIN, and the CENTRAL NERVOUS SYSTEM.	Abufène,Alanine, L-Isomer,L-Alanine,Alanine, L Isomer,L Alanine,L-Isomer Alanine
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001692	Biological Transport	The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.	Transport, Biological,Biologic Transport,Transport, Biologic