Biomaterial Database

Apical membrane aminopeptidase appears at site of cell-cell contact in cultured kidney epithelial cells. 1980

D Louvard

A dog kidney epithelial cell line (MDCK), grown in monolayer, displayed in vitro an asymmetric localization of surface proteins. Aminopeptidase [alpha-aminoacylpeptide hydrolase (microsomal), EC 3.4.11.2] was found only in the apical face whereas Na+, K+-ATPase (ATP phosphohydrolase, EC 3.6.1.3) was found in the basolateral faces. These two faces are delineated by the junctional complex at which close cell-cell contact occurs. alpha-Actinin, a protein associated with plasma membranes, was concentrated near the region of cell-cell contact. When membrane proteins in the apical surface were crosslinked and subsequently removed from the surface by endocytosis, crosslinked antigens reappeared in the apical face at the region of cell-cell contact. Antigens that were not crosslinked were also (re)inserted in the same region. This process was not affected by cycloheximide, presumably because a large pool of apical membrane proteins (observed in small cytoplasmic vesicles) was used to replace the endocytosed antigens. It is psoposed that the region containing the junctional complex is involved in guiding apical membrane proteins to their final location.

UI	MeSH Term	Description	Entries
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D008565	Membrane Proteins	Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.	Cell Membrane Protein,Cell Membrane Proteins,Cell Surface Protein,Cell Surface Proteins,Integral Membrane Proteins,Membrane-Associated Protein,Surface Protein,Surface Proteins,Integral Membrane Protein,Membrane Protein,Membrane-Associated Proteins,Membrane Associated Protein,Membrane Associated Proteins,Membrane Protein, Cell,Membrane Protein, Integral,Membrane Proteins, Integral,Protein, Cell Membrane,Protein, Cell Surface,Protein, Integral Membrane,Protein, Membrane,Protein, Membrane-Associated,Protein, Surface,Proteins, Cell Membrane,Proteins, Cell Surface,Proteins, Integral Membrane,Proteins, Membrane,Proteins, Membrane-Associated,Proteins, Surface,Surface Protein, Cell
D002448	Cell Adhesion	Adherence of cells to surfaces or to other cells.	Adhesion, Cell,Adhesions, Cell,Cell Adhesions
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D004705	Endocytosis	Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis.	Endocytoses
D004848	Epithelium	The layers of EPITHELIAL CELLS which cover the inner and outer surfaces of the cutaneous, mucus, and serous tissues and glands of the body.	Mesothelium,Epithelial Tissue,Mesothelial Tissue,Epithelial Tissues,Mesothelial Tissues,Tissue, Epithelial,Tissue, Mesothelial,Tissues, Epithelial,Tissues, Mesothelial
D000185	Actinin	A protein factor that regulates the length of R-actin. It is chemically similar, but immunochemically distinguishable from actin.	alpha-Actinin,Eu-Actinin,beta-Actinin,Eu Actinin,alpha Actinin,beta Actinin
D000626	Aminopeptidases	A subclass of EXOPEPTIDASES that act on the free N terminus end of a polypeptide liberating a single amino acid residue. EC 3.4.11.	Aminopeptidase