Biomaterial Database

Isolation and partial characterization of the insulin binding sites of Tetrahymena pyriformis. 1995

G K Christopher, and C A Sundermann

Department of Zoology & Wildlife Sciences, Auburn University, AL 36849, USA.

The free-living protozoan, Tetrahymena pyriformis, has been shown to specifically bind insulin. Insulin causes alterations in metabolic function and an increase in insulin binding capacity (hormonal imprinting) in this organism. Previously, an insulin-like material was found in both Tetrahymena cell isolates and in their growth media. The purpose of this study was to isolate and partially characterize the ciliary membrane binding sites for insulin. The methods employed, DEAE and affinity chromatography, were published previously for the mammalian insulin receptor. Here we report, not the isolation of a mammalian-like receptor protein, but a ciliary membrane protein (62-67 kDa) that is immunologically similar to insulin. This insulin-like protein may function as both precursor to a soluble form and membrane-bound binding site/receptor as has been suggested for Euplotes pheromones and mammalian growth factors such as transforming growth factor a and epidermal growth factor.

UI	MeSH Term	Description	Entries
D007328	Insulin	A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1).	Iletin,Insulin A Chain,Insulin B Chain,Insulin, Regular,Novolin,Sodium Insulin,Soluble Insulin,Chain, Insulin B,Insulin, Sodium,Insulin, Soluble,Regular Insulin
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D011972	Receptor, Insulin	A cell surface receptor for INSULIN. It comprises a tetramer of two alpha and two beta subunits which are derived from cleavage of a single precursor protein. The receptor contains an intrinsic TYROSINE KINASE domain that is located within the beta subunit. Activation of the receptor by INSULIN results in numerous metabolic changes including increased uptake of GLUCOSE into the liver, muscle, and ADIPOSE TISSUE.	Insulin Receptor,Insulin Receptor Protein-Tyrosine Kinase,Insulin Receptor alpha Subunit,Insulin Receptor beta Subunit,Insulin Receptor alpha Chain,Insulin Receptor beta Chain,Insulin-Dependent Tyrosine Protein Kinase,Receptors, Insulin,Insulin Receptor Protein Tyrosine Kinase,Insulin Receptors
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
D002846	Chromatography, Affinity	A chromatographic technique that utilizes the ability of biological molecules, often ANTIBODIES, to bind to certain ligands specifically and reversibly. It is used in protein biochemistry. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Chromatography, Bioaffinity,Immunochromatography,Affinity Chromatography,Bioaffinity Chromatography
D002848	Chromatography, DEAE-Cellulose	A type of ion exchange chromatography using diethylaminoethyl cellulose (DEAE-CELLULOSE) as a positively charged resin. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	DEAE-Cellulose Chromatography,Chromatography, DEAE Cellulose,DEAE Cellulose Chromatography
D002923	Cilia	Populations of thin, motile processes found covering the surface of ciliates (CILIOPHORA) or the free surface of the cells making up ciliated EPITHELIUM. Each cilium arises from a basic granule in the superficial layer of CYTOPLASM. The movement of cilia propels ciliates through the liquid in which they live. The movement of cilia on a ciliated epithelium serves to propel a surface layer of mucus or fluid. (King & Stansfield, A Dictionary of Genetics, 4th ed)	Motile Cilia,Motile Cilium,Nodal Cilia,Nodal Cilium,Primary Cilia,Primary Cilium,Cilium,Cilia, Motile,Cilia, Nodal,Cilia, Primary,Cilium, Motile,Cilium, Nodal,Cilium, Primary
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs