RUI: Investigating the Molecular Mechanisms of Non-muscle Myosin II Contractility

Reed College, Portland OR

Investigators

Abstract

The ability of cells to change shape, a process known as morphogenesis, is a fundamental principle of life. Morphogenesis is particularly important during development, and is needed to generate the various layers of tissues that eventually comprise multi-cellular organisms. Cells change shape using a contractile system composed of a network of filaments known as the cytoskeleton, and a molecular motor that pulls on these filaments known as non-muscle myosin II. This research addresses when and where this contractile system is activated and what other potential proteins may regulate this activity. To answer these questions, the research team will use a cell-based system to study the morphogenesis that occurs during development, coupled with computational approaches that will allow for the discovery of new proteins that may play a role in regulating the cytoskeleton, non-muscle myosin II, or both. This research will uncover how this crucial process, morphogenesis, is regulated while also producing computational tools that can be broadly applied to other research questions in the community. The Broader Impact activities includes the formation of a research team composed primarily of undergraduate students who will be mentored in a highly collaborative environment that will foster critical thinking and experiential learning. The students will receive a broad, multi-disciplinary training which will help to prepare them for a variety of science-affiliated career paths. A workshop on Quantitative Biology will also be held for researchers in the Northwest Contractility generated by Non-muscle Myosin II (NMII) is a fundamental cellular process that occurs during cell migration and division. It is particularly important to morphogenesis, or the cell shape change that occurs during development. While many of the kinetic and biophysical properties of NMII are well known, the molecular cues dictating when and where it is activated are far less well understood. What is also lacking is a complete list of the molecules involved in the regulation filament dynamics and contractility. The objective of this project is to dissect the recruitment and activation of NMII through the analysis of a novel NMII regulatory molecule RN-tre. With RN-tre as an example, the project will identify additional regulators of NMII contractility during apical constriction, a critical morphogenic process. Drosophila tissue culture cells will be used to establish an in vitro apical constriction assay by taking advantage their sensitivity to RNAi depletion and confined geometry, making them ideal for high-resolution imaging techniques such as total internal reflection microscopy (TIRF). This project will also develop a computational framework for prioritizing candidate NMII regulators, enabling the testing of the predicted proteins using the apical constriction assay. Along with furthering the understanding of how the critical developmental process is regulated, this project will also produce valuable computational tools that can help answer other complex biological questions. The results of these studies will advance knowledge in the fields of cell and developmental biology by extending our understanding of the mechanisms that regulate NMII contractility.