Biomaterial Database

Characterization of an insulin receptor in human Y79 retinoblastoma cells. 1985

M A Yorek, and A A Spector, and B H Ginsberg

Cultured human Y79 retinoblastoma cells bind [125I]iodoinsulin in a manner similar to that of other CNS and peripheral tissues. The only difference noted between the insulin binding properties of the Y79 cells and other CNS preparations is that insulin binding to Y79 cells is down-regulated by prolonged exposure of the cells to insulin. By contrast, studies with the various brain preparations indicate that the brain insulin receptor is not down-regulated by circulating levels of insulin. Insulin binding to Y79 cells exhibits negative cooperativity, has a pH optimum of 7.8, is responsive to cations, and gives a curvilinear Scatchard plot. Y79 cell insulin binding capacity is 26 fmol/100 micrograms of cell protein, corresponding to about 125,000 binding sites per cell. These findings are the first to report insulin binding in a human cell line of retinal origin. The characterization of the insulin binding in this cell line may facilitate an understanding of the relationship between insulin and its specific functions in the human retina.

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
D007700	Kinetics	The rate dynamics in chemical or physical systems.
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
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D005134	Eye Neoplasms	Tumors or cancer of the EYE.	Cancer of Eye,Eye Cancer,Cancer of the Eye,Neoplasms, Eye,Cancer, Eye,Cancers, Eye,Eye Cancers,Eye Neoplasm,Neoplasm, Eye
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D001667	Binding, Competitive	The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.	Competitive Binding
D012175	Retinoblastoma	A malignant tumor arising from the nuclear layer of the retina that is the most common primary tumor of the eye in children. The tumor tends to occur in early childhood or infancy and may be present at birth. The majority are sporadic, but the condition may be transmitted as an autosomal dominant trait. Histologic features include dense cellularity, small round polygonal cells, and areas of calcification and necrosis. An abnormal pupil reflex (leukokoria); NYSTAGMUS, PATHOLOGIC; STRABISMUS; and visual loss represent common clinical characteristics of this condition. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2104)	Glioblastoma, Retinal,Glioma, Retinal,Neuroblastoma, Retinal,Eye Cancer, Retinoblastoma,Familial Retinoblastoma,Hereditary Retinoblastoma,Sporadic Retinoblastoma,Cancer, Retinoblastoma Eye,Cancers, Retinoblastoma Eye,Eye Cancers, Retinoblastoma,Familial Retinoblastomas,Glioblastomas, Retinal,Gliomas, Retinal,Hereditary Retinoblastomas,Neuroblastomas, Retinal,Retinal Glioblastoma,Retinal Glioblastomas,Retinal Glioma,Retinal Gliomas,Retinal Neuroblastoma,Retinal Neuroblastomas,Retinoblastoma Eye Cancer,Retinoblastoma Eye Cancers,Retinoblastoma, Familial,Retinoblastoma, Hereditary,Retinoblastoma, Sporadic,Retinoblastomas,Retinoblastomas, Familial,Retinoblastomas, Hereditary,Retinoblastomas, Sporadic,Sporadic Retinoblastomas