Overview ? The importance of mechanical forces in cell biology, in addition to chemical and genes, is increasingly appre- ciated. My laboratory focuses on molecular mechanical systems that are implicated in diseases. Malaria parasite invasion is a mechanical event that is powered by an active machinery, known as the ?glideosome?. The current working model of glideosomes postulates that mechanical forces are generated by highly dynamic actin-myosin interactions inside the par- asites. These forces are applied to proteins at the interface between the parasite and the host-cell. The project has two overall goals: 1) to reconstitute mechanical aspects of host-cell invasion by malaria parasites; 2) to understand how force exerted on both the parasite and the host-cell are orchestrated, while persistently bearing the load associated to the malaria parasite moving into the host cell. Innovation ? Current reconstitution approaches lacks the spatial context at nanometer scale. The exquisite positional con- trol of DNA nanotechnology enables precise organization of proteins at molecular resolution. Here, we attach DNA ?handles? to proteins of interest for placement at user-speci?ed locations on programmable DNA scaffolds. The P.I.`s recent research demonstrates that this strategy enables scientists to ?arrange the previously untouchable? and effectively manipulate the interplay between the mechanical and biochemical interactions driving the ensemble behavior. Tools from single-molecule biophysics, protein engineering, and DNA nanotechnology will be used to reconstitute glideo- some outside the complex cellular environments. DNA origami scaffolds will be used to reconstitute mechanical aspects of host-cell invasion by malaria parasites. The number of essential components of the glideosome is relatively small, which makes the system attractive for bottom up reconstitution. Given most of the components are identi?ed and characterized to some extent, we are uniquely positioned to use the programmable DNA scaffolds for investigating the dynamics of the glideosome. This interdisciplinary approach is broadly applicable for dissecting other protein-protein interactions under mechanical tensions.
/Relevance We propose to engineer programmable DNA scaffolds to dissect mechanical processes involved in disease pathogenesis, such as malaria parasite invasion into host cells. The DNA scaffolds simultaneously induce, tune, and measure the tension across proteins of interest. If successful, the proposed work will provide evidences of mechanical forces as a fundamental factor, alongside biochemical interactions and genetic information, in controlling biological functions with profound scienti?c and medical implications.