Dynamics and signal multiplicity in the G protein network

All cells are capable of recognizing and responding to signals from their environment. The molecular machinery that carries out this recognition and response has been well described for many signals, and it is recognized that interacting networks of signaling pathways exist. However, a central problem in cell biology is the manner in which these signaling networks interact and are controlled and integrated to produce an appropriate response to multiple signals. This project will explore the design principles of signaling networks that allow cells to process information that includes both the strength and duration of external signals. Experimental and mathematical modeling approaches will be used to gain a systems-level understanding of multiple signal sensing in a plant (Arabidopsis) well-suited to the study of responses to changes in the environment. A new teaching tool for High School students and the curricular materials for their teachers will be created that make explicit the underlying mathematical principles that will allow students of biology to develop and manipulate models of cell signaling.

This project will establish systems-level properties of the glucose/pathogen (PAMP) sensing system of Arabidopsis, building on the emergent property of 'dose-duration reciprocity' formulated using the glucose response in the heterotrimeric G protein pathway. The specific aims of the project address 1) The emergent properties conferred by network architecture on the glucose response systems, 2) the manner in which multiple signals can operate through a single complex to generate different outcomes, and 3) the manner in which the dynamics of subcellular location of system components regulate the cellular response outcomes.