Biomaterial Database

Cell surface and metabolic labelling of the proteins of normal and transformed chicken cells. 1976

D R Critchley, and J A Wyke, and R O Hynes

We have studied the surface proteins of normal and transformed chick cells using four-labelling techniques with different specificities, (a) lactoperoxidase catalysed iodination (b) galactose oxidase/B3H4 (c) pyridoxal phosphate/B3H4 and (d) periodate/B3H4. All methods labelled a large external transformation-sensitive (LETS) protein, in agreement with previous studies. In addition, using galactose oxidase and periodate labelling techniques, we present evidence which suggests that the transformed cell surface glycoproteins are more sialylated. The LETS protein was also labelled with (14C) glucosamine and after trypsinization a small band of identical molecular weight to LETS remained, possibly representing an internal pool of the protein. In contrast LETS protein labelled with (3H) fucose was completely removed by trypsin, suggesting that the internal pool of the protein is incompletely glycosylated. Evidence is also presented to show that although the level of the protein is drastically reduced at the transformed cell surface, it is still synthesised and shed into the medium.

UI	MeSH Term	Description	Entries
D007784	Lactoperoxidase	An enzyme derived from cow's milk. It catalyzes the radioiodination of tyrosine and its derivatives and of peptides containing tyrosine.
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D009439	Neuraminidase	An enzyme that catalyzes the hydrolysis of alpha-2,3, alpha-2,6-, and alpha-2,8-glycosidic linkages (at a decreasing rate, respectively) of terminal sialic residues in oligosaccharides, glycoproteins, glycolipids, colominic acid, and synthetic substrate. (From Enzyme Nomenclature, 1992)	Sialidase,Exo-alpha-Sialidase,N-Acylneuraminate Glycohydrolases,Oligosaccharide Sialidase,Exo alpha Sialidase,Glycohydrolases, N-Acylneuraminate,N Acylneuraminate Glycohydrolases,Sialidase, Oligosaccharide
D010504	Periodic Acid	A strong oxidizing agent.	Paraperiodic Acid,Periodic Acid (HIO4),Periodic Acids,Acid, Paraperiodic,Acid, Periodic,Acids, Periodic
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D011732	Pyridoxal Phosphate	This is the active form of VITAMIN B 6 serving as a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate (PYRIDOXAMINE).	Pyridoxal 5-Phosphate,Pyridoxal-P,Phosphate, Pyridoxal,Pyridoxal 5 Phosphate,Pyridoxal P
D001894	Borohydrides	A class of inorganic or organic compounds that contain the borohydride (BH4-) anion.	Borohydride
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
D002471	Cell Transformation, Neoplastic	Cell changes manifested by escape from control mechanisms, increased growth potential, alterations in the cell surface, karyotypic abnormalities, morphological and biochemical deviations from the norm, and other attributes conferring the ability to invade, metastasize, and kill.	Neoplastic Transformation, Cell,Neoplastic Cell Transformation,Transformation, Neoplastic Cell,Tumorigenic Transformation,Cell Neoplastic Transformation,Cell Neoplastic Transformations,Cell Transformations, Neoplastic,Neoplastic Cell Transformations,Neoplastic Transformations, Cell,Transformation, Cell Neoplastic,Transformation, Tumorigenic,Transformations, Cell Neoplastic,Transformations, Neoplastic Cell,Transformations, Tumorigenic,Tumorigenic Transformations
D002642	Chick Embryo	The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.	Embryo, Chick,Chick Embryos,Embryos, Chick