Abstract
The APS adapter protein is rapidly tyrosine‐phosphorylated following insulin stimulation. In insulin‐stimulated 3T3‐L1 adipocytes, APS co‐precipitated with phosphorylated c‐Cbl. In CHO.T‐APS cells overexpressing the insulin receptor and APS, APS co‐precipitated with c‐Cbl but not in CHO.T cells which do not express APS. APS‐mediated recruitment of c‐Cbl to the insulin receptor led to rapid ubiquitination of the insulin receptor β‐subunit in CHO.T‐APS but not in parental CHO.T cells. These results suggest that the function of APS is to facilitate coupling of the insulin receptor to c‐Cbl in order to catalyse the ubiquitination of the receptor and initiation of internalisation or degradation.

This publication has 29 references indexed in Scilit: