A novel GTP-binding protein, GIR, along with insulin receptor (IR), has been partially purified from human placenta. A non-hydrolyzable substrate, GTPγS which is known to bind to GTP-binding proteins with high affinity, reduces insulin binding to IR-GIR fraction by approximately 29% and 100 nM insulin stimulates GTPγS binding to IR-GIR fraction by approximately five-fold. The molecular weight of the protein (may be subunit) that binds to 8-azido-GTP, a photoaffinity label for G-proteins, is approximately 66,000.
|Original language||English (US)|
|Number of pages||6|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Dec 14 1990|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology