RUI: Exploring the Structural Basis of Dynein Regulation

Researchers from Lewis & Clark College are studying the motor protein dynein to gain insights into how its function is regulated. Motor proteins serve a number of functions in the cell, including helping transport biological molecules (cargo) to where they belong. One such motor protein, dynein, is important for moving cargo from the periphery toward the center of the cells. In human cells, dynein needs to partner with another protein (dynactin) to move cargo across long distances, such as along nerve cells. The control or regulation of how these two proteins interact determines what, when, and where cargo is transported in a cell. The research team will focus on dynein intermediate chain, a part of dynein that initiates binding with dynactin, and will study how variations in its sequence and the addition of phosphate chemical groups change its binding behavior. New biophysical techniques for studying challenging systems like the dynein/dynactin complex will be developed and used to shine light on how dynein misregulation is involved in disease, an issue with potentially important biotechnology implications. The project provides undergraduate and high school students with opportunities to do research through internships and creates course-based undergraduate research experiences. The research focuses on the interactions between dynein intermediate chain (IC) and its binding partners with the goal of developing a structural model for how an intrinsically disordered region of IC binds with a coiled-coil region of the p150Glued subunit of dynactin. These studies will lead to insights into how this interaction is regulated by the isoform type and phosphorylation state of IC. The study of the interaction by cryo-electron microscopy or X-ray crystallography is difficult due to the dynamic nature of this system. In addition, the complex has characteristics that make it unfavorable for study by conventional NMR methods. The researchers will use mutagenesis to develop smaller, more tractable constructs of p150Glued that will provide high-resolution structural information of the IC/p150Glued complex. This work will complement studies of the less dynamic regions of the dynein complex and will advance the understanding of how the system is regulated. New methods for protein NMR spectroscopy will be developed to benefit researchers studying dynein and intrinsically disordered proteins as well as the protein NMR community at large. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.