Figure 2.

Labeling of insulin receptor subunits with [³²P]orthophosphate. Rat hepatoma (Fao) cells were labeled biosynthetically with [³⁵S]methionine or [³²P]orthophosphate and then incubated in the absence or presence of 1 µM insulin for 15 min. Cell lysates were then prepared and subjected to immunoprecipitation with antibodies to the insulin receptor (B-2) followed by SDS-PAGE under reducing conditions.