CycLex® Protein Tyrosine Phosphatase 1B (PTP1B) Fluorometric Assay Kit
This Kit is a fluorometric and non-radioactive assay designed to measure the activity of protein tyrosine phosphatase, especially Protein Tyrosine Phosphatase 1B (PTP1B).
CycLex® Protein Tyrosine Phosphatase 1B (PTP1B) Fluorometric Assay Kit Specifications
|Background:||The protein-tyrosine phosphatase PTP1B, a ubiquitous, non-transmembrane protein tyrosine
phosphatase, is responsible for negatively regulating insulin signaling by dephosphorylating the
phosphotyrosine residues of the insulin receptor kinase.
Elchebly et al. (1999) generated PTP1B-deficient mice by targeted disruption of the mouse homolog
of the PTP1B gene. Mice were phenotypically and pathologically normal and had normal life span. In
the fed state, homozygous mutant mice had slightly lower blood glucose concentrations, and half the
circulating insulin concentrations, of wild type littermates. The enhanced insulin sensitivity of
PTP1B-deficient mice was also evident in glucose- and insulin-tolerance tests. After insulin injection,
deficient mice showed increased phosphorylation of the insulin receptor in liver and muscle tissue
compared to wild type mice. On a high-fat diet, PTP1B-deficient mice were resistant to weight gain and
remained insulin sensitive, while wild type mice rapidly gained weight and became insulin resistant.
These results suggested a major role for PTP1B in modulation of insulin sensitivity and fuel metabolism,
possibly involving PTP1b regulation of the leptin receptor pathway. Therefore it has been proposed that
PTP1B is a potential therapeutic target for the treatment of type II diabetes and obesity.
Measurement of Protein Tyrosine Phosphatase 1B activity
The CycLexÃ‚Â® PTP1B Fluorometric Assay Kit is based on an exclusive fluorescence substrate and
development reagent combination. This homogenous assay kit is highly sensitive and convenient. This
new method of measurement should dramatically raise the efficiency of inhibitor screening and
biochemical analysis of these enzymes. The principle of the assay is as follows:
1) First, Fluoro-Phospho-Substrate, which comprises a unique PTP substrate containing a phospho group,
is incubated with human PTP1B enzyme (residues 1-322; M.W. 37, 400, expressed in E. coli).
2) Dephosphorylation of the substrate sensitizes the substrate so that, in the second step, treatment with
the Development solution produces a fluorophore.
3) The fluorophore can be easily analyzed with a fluorescence plate reader or a fluorometer. The assay is
suitable for high throughput screening applications.
|Regulatory Statement:||For Research Use Only. Not for use in diagnostic procedures.|
|Kit Components:||10X PTP Assay Buffer, 10X Fluoro-Phospho-Substrate, Recombinant Human PTP1B, Development Buffer, Development Reagent, Stop Solution, PTP1B Inhibitor, 10X Fluoro-Non-Phospho-Substrate|
- Iwakami S, et al., PLoS One, 6, e27401 (2011)