Biological systems are networks and in these networks, we can define nodes (e.g., genes, proteins, metabolites) connected through edges (e.g., enzymatic/chemical reactions, transcription regulation). Networks have properties that can be measured using a mathematical approach, and we can make predictions about the evolution of a system based on some of those properties.

A “pathway” in a biological system can be defined as a relatively discrete (though never completely isolated) portion of a network. Generally, we view a pathway as a sequence of gene regulatory and enzymatic reactions that produce some important biological outcomes (e.g., synthesize an energy storage molecule, sense and regulate blood sugar levels).

In this project we will be using network analysis approaches to better understand the evolution and function of biological pathways. The Pathways Project is focused on annotating genes found in well characterized signaling and metabolic pathways across the Drosophila genus. The current focus is on the insulin signaling pathway which is well conserved across animals and critical to growth and metabolic homeostasis. The long-term goal of the Pathways Project is to analyze how the regulatory regions of genes evolve in the context of their positions within a network and we anticipate that other pathways will eventually be part of the analyses.