Tyrosine antibodies

Kinase or phosphatase assays based on the AlphaScreen principle are similar to TR-FRET assays in that they usually require a biotinylated substrate peptide and an anti-phosphoserine or tyrosine antibody. These two reagents are sandwiched between biotin and protein A-functionalized acceptor and donor beads. A kinase assay would show an enzyme-dependent increase in antibody binding (and thus signal) over time and a phosphatase assay would show an enzyme-dependent decrease in antibody binding over time. In some cases, the phosphorylation of an epitope will block the antibody binding and thus a phosphatase assay in principle can be constructed as a signal increase assay (Von Leoprichting and Kumpf, 2004 Warner et al., 2004). 

Antibodies to OP-tyrosine will be made. These antibodies will be used to diagnose OP exposure in a biosensor assay with saliva, sweat, or urine. New biomarkers of OP exposure will be identified using mass spectrometry and the new OP-tyrosine antibodies. The identification of new biomarkers for low-dose OP exposme is expected to lead to an understanding of how neurotoxicity is caused by OP doses that are too low to inhibit acetylcholinesterase. For example, it is possible that disruption of microtubule polymerization by OP-adduct formation may explain cognitive impairment from OP exposure. 

The work flow for dPLIMSTEX starts with half the volume of an equilibrated protein-peptide complex for measurement. The other half is diluted in aqueous buffer before incubation (Figure 11.5). The dilution step is continued until the concentration of the peptide is too low to be detected. dPLIMSTEX was first demonstrated by using a model system, calcium-saturated calmodulin with the opioid peptide )-endorphin it yielded a similar binding constant as that determined by standard PLIMSTEX and other methods. dPLIMSTEX was then applied to a monoclonal antinitro-tyrosine antibody, in complex with a 3-nitrotyrosine-modified peptide system. A binding stoichiometry of 1 2 was confirmed. In addition, a in the low nM range and a minimum of five amino... 

The epidermal growth factor receptor 2 (HER-2) is a protein found on the surface of cells. Heterodimerization of HER-2 activates the enzyme tyrosine kinase, triggering reactions that cause the cells to grow and multiply. HER-2 is found at abnormally high levels on the surface of many types of cancer cells, which may divide excessively. Antibodies targeting HER-2 (e.g., trastuzumab) are used as antineoplastic agents. 

Main differences between monoclonal antibodies and small-molecule receptor tyrosine kinases are described in Table 2. 

Monoclonal antibodies Small-molecule tyrosine kinase inhibitors... 

TKIs (tyrosine kinase inhibitors) Kinase inhibitors Monoclonal antibodies... 

The enzyme /i-phenylethanolamine-A-methyl transferase, which is required to convert noradrenaline (NA) to adrenaline (Ad), is present in the CNS and there is histofluoro-metric evidence (positive staining with antibodies to that enzyme and to tyrosine hydroxylase and dopamine /i-hydroxylase as well) for adrenergic cell bodies in two groups (nuclei) alongside NA neurons of the locus coeruleus (EC) but ventral and lateral (Ci) and dorsal and medial (C2) to it. Projections go to the hypothalamus and in... 

ATLURU s, ATLURU D (1991) Evidence that genistein, a protein-tyrosine kinase inhibitor, inhibits CD28 monoclonal antibody stimulated human T-cell proliferation. Transplantation. 51 448-50. 

Figure 4. DDC (A), serotonin (B), and tyrosine hydroxylase (C) immunore-activity in the posterior region of a wild-type Drosophila ventral ganglion. Tyrosine hydroxylase (TH) encodes the rate-limiting step in dopamine biosynthesis and is a marker for dopamine cells. B and C are the same CNS assayed for both serotonin and TH. M, medial dopamine neurons VL, ventrolateral serotonin neurons DL, dorsolateral dopamine neurons. Short unmarked arrows in C show vacuolated cells that do not contain DDC immunoreactivity. The immunoreactivity in these cells may represent a nonspecific cross-reactivity of the rat TH antibody. The length bar in A is 50 pM. The images are confocal projections generated on a Molecular Dynamics-2000 confocal laser scanning microscope.

Mailer Have you used these new phospho-specific antibodies to Cdc2 to examine the cycles of tyrosine phosphorylation and dephosphorylation ... 

Figure 16.3 Conceptual illustration of two peptides before (left) and after (right) a chemical reaction with formaldehyde. The amino acids are represented as circles. In this particular peptide, a tyrosine (Y) is located within the epitope (shaded circles). An arginine (R) is located elsewhere in the peptide. Formaldehyde results in the formation of a covalent bond between the two residues, due to a Mannich condensation reaction, as shown on the right. The new configuration prevents antibodies from binding to the epitope on the left. 

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