Model of interaction of the IL-1 receptor accessory protein IL-1RAcP with the IL-1β/IL-1RI complex

A preliminary model has been calculated for the activating interaction of the interleukin 1 receptor (IL-1R) accessory protein IL-1RAcP with the ligand/receptor complex IL-I beta /IL-1R(1). First, IL-1RAcP was modeled on the crystal structure of IL-1R(1) bound to IL-1 beta. Then, the IL-1RAcP model was docked using specific programs to the crystal structure of the IL-1 beta /IL-1R(1) complex. Two types Of models were predicted, with comparable probability, Experimental data obtained with the use of IL-1 beta peptides and antibodies, and with mutated IL-1 beta proteins, support the BACK model, in which IL-1RAcP establishes contacts with the bark of IL-1R(1) wrapped around IL-1 beta. (C) 2001 Federation of European Biochemical Societies, Published by Elsevier Science B.V. All rights reserved.