{HEAD ~ IRS1} and IRS2 are part of the insulin or insulin like growth factor signaling {TAIL ~ pathway} 
{ HEAD ~ IRS1 } and IRS2 are part of the insulin or insulin like growth factor signaling { TAIL ~ pathway }
HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL