The ability of subsets of cells to form new cells with different characteristics is fundamental to biological processes such as embryonic development, tissue regeneration, and wound healing and depends on changes in the expression of a cell’s genes. Gene expression is guided by proteins called transcription factors. The transcription factor TWIST is important for the formation of different cell types by helping induce changes that cause epithelial cells to become mesenchymal cells during the epithelial to mesenchymal transition (EMT). Although EMT is required for proper organ development, EMT also endows cells with potentially detrimental migration and invasion properties, and thus must be tightly regulated. This project will provide a better understanding of how EMT is controlled by defining specific mechanisms that change the molecular structure and activity of TWIST by using a novel platform to rapidly identify proteins that recognize these changes in molecular structure. Overall, the project will also provide an ideal opportunity for the training of graduate students and postdoctoral scientists in molecular biology and proteomics, as well as introducing elementary, high school, and undergraduate students, particularly those in underrepresented minority groups, to basic science research and advanced technology. In addition, this project will provide science, technology, engineering, and math (STEM) opportunities in a rural area with few options for students with STEM interests through established educational and community outreach programs.
Information is relayed from the cell surface into the nucleus through the process of signal transduction. Signal transduction is driven by protein interactions that are controlled by posttranslational modifications (PTM). Typically, a specific protein domain on one protein recognizes or “reads†the PTM signal present on its interacting partners. This project will address fundamental questions regarding the crosstalk between PTMs in the regulation of transcriptional programs that govern EMT. A recently discovered regulatory node on the transcription factor TWIST1 potentially harbors a combinatorial code consisting of three distinct PTMs that occur within six amino acid residues of each other. The code is established through lysine and arginine methylation by SETD6 and PRMT1, respectively, and lysine ubiquitinylation by RNF8. The project seeks to define the molecular crosstalk among these enzymes, and how they function to promote EMT through TWIST1. An important part of dissecting the molecular mechanism of signaling through this methyl/ubiquitin node on TWIST1 is a novel protein domain microarray platform that will be used to rapidly identify protein-protein interactions dependent upon specific PTMs and combinations of PTMs. This platform will help answer fundamental questions including: 1) which protein domains bind each of these different PTMs in the TWIST1 methyl/ubiquitin regulatory node; and 2) whether specific combinations of these PTMs block or facilitate protein interactions? This study will provide not only a basic mechanistic understanding of how the distinct PTMs on TWIST regulate each other, and how they regulate interactions with other proteins, in the context of EMT, but also a broader perspective on how PTMs might regulate protein-protein interactions in general.
This collaborative US/Israel project is supported by the US National Science Foundation and the Israeli Binational Science Foundation.
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.
