Transient gene expression in petunia flower petals as a toolbox

ABSTRACTAgroinfiltration-mediated transient expression is widely used in plant gene functional studies. In this study, the functionality of a metabolic engineering construct containing multiple expression cassettes for betalain biosynthesis genes was validated via agroinfiltration in petunia flower petals. The effects of transcription factors that upregulate anthocyanin biosynthesis and a gene that regulates cellular pH were also demonstrated on petunia petals by agroinfiltration. We also showed that flower petal agroinfiltration is a quick approach to test gene editing components, e.g. different guide RNAs. In general, the agroinfiltration-mediated transient transformation in flower petals is a great tool for testing flowering colour–related trait genes, as well as for optimising gene editing components.KEYWORDS: Agro-infiltrationPetunia x hybridaflower petaltransient expressiongene editing AcknowledgementsThe author thanks Mrs. Sharon Jhingory-Ahmad for her help with the experiments and proofreading.Disclosure statementNo potential conflict of interest was reported by the author.Data availability statementThe author confirms that the data supporting the findings of this study are available within the article and/or its supplementary materials.Additional informationFundingThe manuscript was supported by the United States Department of Agriculture (USDA) - Agriculture Research Service (ARS) Base funds to Hui Duan.