Collaborative Research: PlantTransform: Morphogenic-based mechanisms of maize regeneration

Inefficient methods for transformation and regeneration of recalcitrant plant species prevent widespread applications of genome editing technologies for both basic and applied research in established and emerging crop species. Overcoming these limitations is particularly relevant in monocotyledonous crops, such as maize, which alone provide most of the calories consumed by humans. In this project, maize lines expressing genes that promote regeneration, also known as morphogenic factors, will be used to provide a thorough understanding of the molecular events leading to the successful formation of new plants starting from differentiated tissue. This knowledge will be instrumental in developing new strategies for improving transformation of maize and other plant species, and will be integrated into course-based undergraduate research experiences (CUREs) as well as hands-on transformation workshops. The proposed research will exploit a morphogenic-based system called “GGB” to understand how certain morphogenic regulators reprogram somatic cells to develop into embryos and identify key regeneration genes that could be targeted to improve transformation efficiency in recalcitrant genetic backgrounds. This will be accomplished by the identification of direct targets of regulation of the GGB components via single-cell transcriptomic and DNA-binding approaches, and by the development of a diverse panel of maize inbred lines expressing the GGB morphogenic regulators. By exploiting the regenerative capacity of this system, protoplast regeneration, a challenging but advantageous system for the rapid generation of non-GMO edited plants, will also be revisited. This research will provide insights into the molecular basis of tissue- and genotype-dependent regeneration, helping to identify and eventually bypass roadblocks to regeneration, and will facilitate the development of high-throughput systems for genome-editing and transgenic line generation in diverse genetic backgrounds. This project is jointly funded by Genetic Mechanisms (BIO-MCB). Emerging Frontiers (BIO), and the Plant Genome Research Program (BIO-IOS). 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.