Dan Dickinson received his bachelor’s degree in biochemistry from Iowa State University. After spending a year in Switzerland as a Fulbright scholar, he earned his Ph.D. at Stanford, where he was jointly advised by James Nelson and Bill Weis. Dan’s Ph.D. thesis work identified an epithelial tissue in Dictyostelium, a non-metazoan organism with a simple multicellular developmental process. This work had significant implications for our understanding of early animal evolution. In 2011, Dan moved to UNC Chapel Hill to join Bob Goldstein’s lab as a postdoc. He has been a leader in developing genome editing methods for C. elegans, but his core interests are in cell biology, with a particular focus on understanding the molecular basis of cell polarity. Dan’s postdoctoral work has been funded by a Helen Hay Whitney foundation fellowship, and more recently by an NIH K99 award.
Single-Cell Approaches and Development: Cell Polarity and the PAR Complex in C. Elegans
Cell polarity is a fundamental feature of eukaryotic cells and plays a major role in the development and homeostasis of animal tissues. The PAR protein system is conserved throughout animals and is a major player in polarization of many different animal cell types. Many in vitro interactions between PAR proteins have been identified, but a major challenge for the field is to understand how these biochemical events are regulated and coordinated in vivo to produce a polarized cell. This challenge is not unique to the cell polarity field; it is a widespread issue in cell biology. I developed a single-molecule approach for performing biochemical assays on individual cells, allowing quantitative measurements of protein-protein interactions in a time-resolved manner in vivo. Applying this approach to C. elegans zygotes undergoing polarization, I identified a tightly regulated PAR protein complex - a large oligomer of the PAR-3 protein - that is essential for polarity establishment. PAR-3 oligomerization facilitates physical coupling of PAR proteins to cortical flows that polarize the cell. These results provide novel insight into how cells spatially segregate polarity determinants, and they establish experimental tools that will advance a comprehensive understanding of the signaling circuitry that mediates animal cell polarization.