Dynamics of the interaction between the insulin receptor and protein tyrosine-phosphatase 1B in living cells.
The dynamics of the interaction of the insulin receptor with a substrate-trapping mutant of protein-tyrosine phosphatase 1B (PTP1B) were monitored in living human embryonic kidney cells using bioluminescence resonance energy transfer (BRET). Insulin dose-dependently stimulates this interaction, which could be followed in real time for more than 30 minutes. The effect of insulin on the BRET signal could be detected at early time-points (30 seconds), suggesting that in intact cells the tyrosine-kinase activity of the insulin receptor is tightly controlled by PTP1B. Interestingly, the basal (insulin-independent) interaction of the insulin receptor with PTP1B was much weaker with a soluble form of the tyrosine-phosphatase than with the endoplasmic reticulum (ER)-targeted form. Inhibition of insulin-receptor processing using tunicamycin suggests that the basal interaction occurs during insulin-receptor biosynthesis in the ER. Therefore, localization of PTP1B in this compartment might be important for the regulation of insulin receptors during their biosynthesis.
Boute
Nicolas
N
Department of Cell Biology, Institut Cochin, CNRS-UMR 8104, INSERM U567, Université Paris V, 22 Rue Méchain, 75014 Paris, France.
Boubekeur
Samira
S
Lacasa
Danièle
D
Issad
Tarik
T
D002478:Cells, Cultured; D018076:DNA, Complementary / Q000235:genetics; D006801:Humans; D007668:Kidney; D007700:Kinetics; D008163:Luminescent Measurements; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1; D017027:Protein Tyrosine Phosphatases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011972:Receptor, Insulin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D014162:Transfection; D018909:src Homology Domains
D018076:DNA, Complementary; D011993:Recombinant Fusion Proteins; D011972:Receptor, Insulin; C516607:PTPN1 protein, human; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1; D017027:Protein Tyrosine Phosphatases