S01 - Session P5 - Molecular characterization of flavonoid biosynthesis factors in two white-flowered cyclamens

Authors: Riho Mikami, Céline Pesteil *, Yusuke Akita

Two white-flowered amphi-diploid cyclamen strains, HA-white (HA) and HB-white (HB), were produced by interspecific hybridization between Cyclamen persicum and C. hedeliforium . To characterize these strains, we analyzed the floral components that related to flower colorations by UPLC/MS/MS analysis. In the petals of HA, two kaempferol-derived flavonols and two quercetin-derived flavonols were detected as the main components. In HB, a higher amount of kaempferol-derived flavonols and a lower amount of quercetin-derived flavonols were identified. Among these flavonols, one quercetin-derived flavonol (quercetin + glucose + rhamnose) was specific to HA, and one kaempferol-derived flavonol (kaempferol + glucose + rhamnose) was only detected in HB. These results suggested that the different factors related to flavonoid biosynthesis would function and/or have mutated in each strain. To determine these factors, we performed RNA-seq analysis and compared the gene expressions between the petals of HA and HB. We found that the expression levels of some flavonoid biosynthesis-related genes were different in each strain. The results of the genomic analysis showed that nucleotide mutations such as base substitution and deletion, did not occur in the candidate genes. We will show the results of comparative analysis and discuss the possibility of the different characters between HA and HB. It is very interesting that there are differences in flavonol types and contents among white flowers that look the same. We hope that we can create flowers of new colors by exploring these causes.