“Development of custom nucleases for genome engineering applications”
12:30 – 1:30pm, Foege N130A (Wallace H. Coulter Seminar Room)
Site-specific nucleases are primary tools for genome engineering. Several customizable nuclease architectures have been developed (CRISPR, TALEN, HEs), each having distinct genetic, structural, and biochemical attributes. Homing endonucleases (HE) are compact, monomeric proteins that efficiently cleave 22 bp DNA target sequences with high specificity. However, HEs use complex DNA recognition and cleavage mechanisms that have confounded attempts to reprogram them toward non-native DNA sequences. We addressed the challenge of reprogramming HEs by developing an informatics-driven modular reassembly approach. Reassembly was guided by a series of comprehensively reprogrammed modules distributed in an overlapping manner along the protein-DNA interface. Combining this approach with novel refinement strategies resulted in HEs that selectively target genomic DNA sequences with nearly complete efficiency in primary cell populations and in organismal tissues. In this talk I will describe our reprogramming approach, and the applications of our HE re-targeting for an HIV curative therapy and Malaria vector control.
Dr. Havens joined Pregenen in July of 2013 and has focused primarily on reprogramming homing endonucleases (HEs) for both Pregenen’s therapeutic development projects and the Gates Grand Challenges in Global Health project involving gene drive strategies for malaria vector control. Dr. Havens obtained his B.S. from Point Loma Nazarene University in San Diego, and his PhD in Genetics from Tufts University in Boston under Dean Dawson, where he studied chromosome segregation mechanisms in yeast. As a postdoctoral researcher in the lab of Eric Klavins at UW, he worked on a joint project with Jennifer Nemhauser’s group to port a plant hormone pathway into yeast to both study signaling network dynamics and generate new synthetic gene expression tools.