Abstract:

Bioengineering of plants is critical to agriculture, molecular farming, and bio-commodities. However, current tools for bioengineering plants are limited in throughput, applicable to a narrow set of species, or automatic triggers for regulatory oversight. Biotechnology tools which enable direct delivery of proteins to plants could simplify the technical and regulatory process of plant bioengineering, yet proteins remain the most challenging cargoes to deliver to plants. In this seminar, I discuss the discovery of a new class of biotechnology tools, derived from plants, capable of delivering a broad range of proteins to plants. First, I introduce fundamental challenges in developing and quantifying the efficiency of biotechnology tools in plants, describing the development of a fluorescence complementation method which addresses these challenges. Leveraging this method, I next discuss the discovery a class of plant proteins called homeoproteins which are natively cell-penetrating, capable of “self-delivery”. By computationally screening tens of thousands of plant homeoproteins, we identify a conserved domain responsible for the ability of homeoproteins to “self-deliver” and synthesize plant-based cell-penetrating peptides (pCPPs) from these domains. Finally, we demonstrate pCPPs efficiently deliver recombinant proteins to plants. This work has broad applications for agricultural biotechnology as well as implications for fundamental plant biology.