CRISPR Cultivates an Arabidopsis Rose Rainbow

While spending a lot of time at his parents’ cabin in the Missouri countryside in his youth, plant biologist Nick Desnoyer found himself fascinated by the surrounding flora. “I remember dissecting plants with my fingers and being like, ‘What is all this mushy stuff?’” That early curiosity eventually led him to the University of Zürich, where he studied plant reproduction by examining the development of pollen grains inside flowers.

In 2023, as Desnoyer considered new ways to engage undergraduate students in a floral development course, inspiration struck. Around the same time, a colleague had the RUBY reporter gene, derived from beetroots, which converts tyrosine to a vivid red betalain pigment.¹ He intended to use it to mark pollen tubes, but Desnoyer became intrigued by the idea of expressing this gene in flower petals instead.

Arabidopsis thaliana has a small genome, making it an ideal model organism for genetic experimentation and floral design. He decided to cross RUBY-expressing A. thaliana with A. thaliana agamous mutants. These mutants lack reproductive organs and produce concentric whorls of sepals and petals, creating a floral form reminiscent of a rose, instead of the classic four, white petals. The final cross produced a pink Arabidopsis rose, an aesthetic demonstration of synthetic biology.

Since then, Desnoyer pursued the Arabidopsis rose as a personal project, enjoying this fusion of artwork and science. “I’ve been CRISPRing and adding in more aesthetic mutations and also trying to play around with different pigmentation patterns.” The above image showcases his creations: various shades of pink- and champagne-colored blooms. The latter were achieved by engineering genes that encode betaxanthin pigments, which produce yellow to orange hues. “It’s quite rewarding, because once you get the plant [and seeds], then you have it for as long as you're a steward to it…because the artwork itself replicates.”

Through this work, Desnoyer aims to develop a practical guide to plant engineering, complete with DNA parts and a toolkit, that students can use for plant design in an academic setting. He’s also incorporating visual elements from previous science communication efforts, including time-lapse microscopy and animations, to make the work more engaging. Now a postdoctoral researcher at The Sainsbury Laboratory, Desnoyer plans to keep pursuing his dream of engineering new floral forms.