Elucidating the role of local auxin biosynthesis in plant regeneration.

The ability of plants to regrow an entire organism from just a few cells is a truly remarkable feat of nature, widely used in agriculture and biotechnology for centuries. For example, methods like taking cuttings from a plant to grow new ones, or grafting different plant parts together, rely on this natural capacity. Modern applications, such as developing improved crop varieties through genetic engineering, also depend heavily on understanding and harnessing this unusual plant characteristic. Despite its importance, the precise molecular mechanisms that allow a differentiated plant cell to essentially "reset" and begin forming a new plant are not fully understood. This project aims to unravel these fundamental processes, which are crucial for overcoming current limitations in developing new and improved plant varieties that can better withstand environmental challenges or produce more food and resources. By understanding how plants regenerate, this research will provide foundational knowledge to improve crops and contribute to a more sustainable future for agriculture. Broader Impact activities will include training of students and outreach to the local community via the Plants4Kids program in North Carolina and Science Bound Saturday events at Iowa State University. This project focuses on elucidating the molecular mechanisms by which somatic plant cells reprogram to regenerate organs and whole plants. While plant hormones, particularly auxin, cytokinin, and ethylene, are known to be critical regulators of this process, the specific roles of local auxin biosynthesis and its interplay with other hormonal and regulatory networks remain largely unexplored. The research aims to: 1) identify specific auxin biosynthetic genes involved in the initial stages of cellular reprogramming using a comprehensive collection of whole-gene translational reporters; 2) determine the functional significance of localized auxin biosynthesis in promoting plant regeneration; and 3) delineate the regulatory networks downstream of these key auxin biosynthetic genes involved in callus formation and subsequent plant regeneration. This will be achieved through single-nuclei RNA-seq analysis at precisely chosen time points, guided by a novel triple hormone response sensor that provides cellular resolution of auxin, cytokinin, and ethylene activities, linking transcriptional changes to morphological events. This award is co-funded by the IOS-Developmental Systems Cluster and the IOS-Physiological Mechanisms and Biomechanics Program. 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.