Light is an important resource for plants, as it serves both as energy and as a signal for growth and development. For this reason, plants have evolved a complex system of signaling pathways to sense and react to light in many conditions. Red and far-red light are detected by photoreceptors called phytochromes. The phytochrome phyB has been the target of mutant studies by Gingerich lab. One of the phyB mutant lines isolated by the lab displays an increased response to both red light and blue light. In this line phyB is predicted to contain a change in a single amino acid as a result of a single nucleotide polymorphism (SNP) in the PHYB gene. To confirm that it is indeed the phyB mutation in this line that is causing the red and blue light phenotypes, we are implementing a CRISPR-Cas9-based gene editing system for Arabidopsis in the lab, with the purpose of recapitulating the PHYB SNP of the mutant line in plants that are otherwise wild-type. The specific system we are using is “prime-editing”. We will detail synthesis of the DNA constructs needed to implement the prime editing and our current efforts to transform plants and initiate the editing process.