Flavonoid 3',5'-Hydroxylase (<i>F3'5'H</i>) Gene Polymorphisms Co-segregate with Variation in Anthocyanin Composition in the Flower Petals of Lisianthus [<i>Eustoma grandiflorum</i> (Raf.) Shinn.]

Abstract

This study investigated genetic polymorphism related to anthocyanin composition variation in lisianthus (Eustoma grandiflorum) flower petals. Three different bands were detected by genomic polymerase chain reaction using specific primers based on the reported flavonoid 3',5'-hydroxylase (F3'5'H) gene sequence. Our genetic study revealed that they were allelic. They were named F3'5'H1-1, F3'5'H1-2, and f3'5'h1-2. F3'5'H1-1 and F3'5'H1-2 differed in the length of the intron. Allele f3'5'h1-2 possessed a retrotransposon insertion in the first exon, but otherwise, its gene sequence was almost identical to that of F3'5'H1-2. This retrotransposon is a Ty1-copia type retrotransposon and was designated as the retrotransposon of Eustoma grandiflorum 1 (rTeg1). The mauve flower line 'ME' and red-purple flower line 'PRP' were homozygous for F3'5'H1-1 and mostly accumulated cyanidin, with a small amount of delphinidin, in flower petals (the Cy major phenotype). The violet flower line 'RV' was homozygous for F3'5'H1-2 and accumulated only delphinidin (the Dp major phenotype). The pink-red flower line 'AK' was homozygous for f3'5'h1-2, accumulated pelargonidin, and lacked delphinidin (the Pg major-non Dp phenotype). Segregation analysis of the F 2 population from 'ME' × 'RV' revealed that F3'5'H1-2 was associated with the Dp major phenotype, and the delphinidin major trait was dominant in the Cy major phenotype. All the Cy major phenotype plants in the F 2 population possessed homozygous F3'5'H1-1. Genetic analysis of the F 2 population from the cross between delphinidin-containing and delphinidin-lacking strains revealed that the homozygous f3'5'h1-2 genotype co-segregated with the Pg major-non Dp phenotype, which was recessive to the delphinidin-containing phenotypes. Expression analysis of the F3'5'H gene demonstrated that an abnormal mRNA was transcribed from the F3'5'H gene in the homozygous f3'5'h1-2 line by the insertion of rTeg1. Therefore, these F3'5'H gene polymorphisms can be used as DNA markers for breeding lisianthus based on flower color.

Genome-Wide Analysis of the F3′5′H Gene Family in Blueberry (Vaccinium corymbosum L.) Provides Insights into the Regulation of Anthocyanin Biosynthesis

“…Sun et al [57] confirmed that the heterologous expression of PCFH belonging to the CYP75B subfamily could produce a kind of delphinidin derivative (3′,5′-hydroxylated anthocyanidins) in vivo and its encoded protein had the 3′,5′-hydroxylation function. Takatori et al [62] found that F3′5′H genes were involved in the synthesis of delphinium in Eustoma grandiflorum (Raf.) Shinn, and of other types of anthocyanins, such as cyanidin-type anthocyanin and pelargonidin-type anthocyanin that produce various flower colors.…”