With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Dr. Ellinor Haglund from the University of Hawaii to investigate the connection between protein topology and biology of a newly identified protein topology, namely the Pierced Lasso Topology (PLT). Here, the amino acid chain forms a lasso, where part of the chain is threaded through. The lasso-forming bond depends on the chemical environment in the cell or the extracellular matrix. The bond can be made or broken under oxidizing and reducing conditions acting like an on/off switch for biological activity. In a combined effort from molecular dynamics simulations, in vitro, and in vivo experiments using Drosophila melanogaster as our genetic model system, the possible role of PLTs acting as a molecular switch controlled by the chemical environment controlling biological activity will be investigated. This project will also be integrated into an outreach program to teach students and non-scientists about topological constraints in nature with clear links to society.