Signalling through the insulin receptor

The insulin receptor substrates function at the heart of the insulin signal ling network. It has recently become apparent that the intracellular locali sation of these molecules is regulated in a precise manner that is critical for both the generation and the termination of the insulin signal. Some in sulin receptor substrate isoforms appear to be associated with an insoluble matrix that resembles the cytoskeleton. When inappropriately dissociated f rom this matrix the signalling network collapses concomitant with loss of i nsulin sensitivity.