Details

Autor(en) / Beteiligte

• Lavan, B.E. (Dartmouth Medical School, Hanover, NH.)
• Lane, W.S
• Lienhard, G.E

Titel

The 60-kDa phosphotyrosine protein in insulin-treated adipocytes is a new member of the insulin receptor substrate family

Ist Teil von

• The Journal of biological chemistry, 1997-04, Vol.272 (17), p.11439-11443

Ort / Verlag

United States: American Society for Biochemistry and Molecular Biology

Erscheinungsjahr

1997

Quelle

MEDLINE

Beschreibungen/Notizen

• A 60-kDa protein that undergoes rapid tyrosine phosphorylation in response to insulin and then binds phosphatidylinositol 3-kinase has been previously described in adipocytes and hepatoma cells. We have isolated this protein, referred to as pp60, from rat adipocytes, obtained the sequences of tryptic peptides, and cloned its cDNA. The predicted amino acid sequence of pp60 reveals that it contains an N-terminal pleckstrin homology domain, followed by a phosphotyrosine binding domain, followed by a group of likely tyrosine phosphorylation sites, four of which are in the YXXM motif that binds to the SH2 domains of phosphatidylinositol 3-kinase. The overall architecture of pp60 is thus the same as that of insulin receptor substrates 1 and 2 (IRS-1 and IRS-2), and furthermore both the pleckstrin homology and phosphotyrosine binding domains are highly homologous (about 50% identical amino acids) to these domains in both IRS-1 and IRS-2. Thus, pp60 is a new member of the IRS family, which we have designated IRS-3