Expression of protein-tyrosine phosphatases in the major insulin target tissues
Research output: Contribution to journal › Journal article › Research › peer-review
Protein-tyrosine phosphatases (PTPs) are key regulators of the insulin receptor signal transduction pathway. We have performed a detailed analysis of PTP expression in the major human insulin target tissues or cells (liver, adipose tissue, skeletal muscle and endothelial cells). To obtain a representative picture, all tissues were analyzed by PCR using three different primer sets corresponding to conserved regions of known PTPs. A total of 24 different PTPs were identified. A multiprobe RNase protection assay was developed to obtain a semiquantitative measure of the expression levels of selected PTPs. Surprisingly, PTP-LAR, previously suggested to be a major regulator of the insulin receptor tyrosine kinase, was expressed in extremely low levels in skeletal muscle, whereas the related receptor-type PTP-sigma and PTP-alpha were expressed in relatively high levels in all four tissues. The low levels of LAR PTP mRNA in skeletal muscle were further confirmed by Northern blot analysis.
|Number of pages||6|
|Publication status||Published - 6 Oct 1997|
- Adipose Tissue, Blotting, Northern, DNA Primers, Endothelium, Vascular, Gene Expression Regulation, Enzymologic, Humans, Isoenzymes, Muscle, Skeletal, Placenta, Polymerase Chain Reaction, Protein Tyrosine Phosphatases, RNA Probes, RNA, Messenger, Receptor, Insulin, Receptor-Like Protein Tyrosine Phosphatases, Class 4, Receptors, Cell Surface, Ribonucleases, Signal Transduction