The functional redundancy test and the parameter sensitivity analysis of crucial proteins in the GPCR signaling network.

Abstract

<p>(A) Functional redundancy in the forward module of the GPCR signaling network. Two pathways being PLC<i>β</i>3 or PLC<i>β</i>4 dependent, fork at G<i>α</i>q-GTP and converge at IP3. Their function shows redundancy since the concentration of IP3 still reaches as much as 80 percent of the original amplitude even if removing one of them from the signaling network. But when they are both removed, signal only reaches half of the original amplitude indicating the complementarity between the two paths in conducting signals. (B) Sensitivity to parameters of the reaction hub in the forward module of the GPCR signaling network. The reaction rate K08 is the synthetic rate of G<i>α</i>q-GTP and G<i>βγ</i>. Both products are essential for signal forwarding.</p