Cloning of cDNA coding for dihydroflavonol-4-reductase (DFR) and characterization of dfr expression in the corollas of Gerbera hybrida var. Regina (Compositae)

Abstract

We are approaching corolla differentiation in Compositae by studying the regulation of flavonoid pathway genes during inflorescence development in gerbera. We have cloned a dfr cDNA from a ray floret corolla cDNA library of Gerbera hybrida var. Regina by a PCR technique based on homologies found in genes isolated from other plant species. The functionality of the clone was tested in vivo by complementing the dihydrokaempferol accumulating petunia mutant line RL01. By Southern blot analysis, G. hybrida var. Regina was shown to harbour a small family of dfr genes, one member of which was deduced to be mainly responsible for the DFR activity in corolla. Dfr expression in corolla correlates with the anthocyanin accumulation pattern: it is basipetally induced, epidermally specific and restricted to the ligular part of corolla. By comparing the dfr expression in different floret types during inflorescence development, we could see that dfr expression reflects developmental schemes of the outermost ray and trans florets, contrasted with that of the disc florets.

A TCP domain transcription factor controls flower type specification along the radial axis of the Gerbera (Asteraceae) inflorescence

“…The developmental stages for inflorescences are described in ref. 37 and for the young developing floral primordia in ref. 3.…”

Flower color modification of Petunia hybrida commercial varieties by metabolic engineering

“…The pelargonidinaccumulating brick red/orange petunia was generated by expression of a maize DFR gene in a petunia that is deficient in F3Ј5ЈH, F3ЈH and FLS activities and accumulates dihydrokaempferol (Meyer et al 1987). The pelargonidin-accumulating brick-red/orange petunia was obtained by expression of a gerbera and a rose DFR gene (Helariutta et al 1993;Tanaka et al 1995).…”

Blood chemistry profile of Bali cattle fed silage rice straw and biosupplement of selected rumen and termites lignocellulolytic bacteria consortium

“…Dihydroflavonol-4-reductase (DFR) is a pivotal enzyme for anthocyanin production 5 .Anthocyaninsare water soluble pigments whose colours depend 6 on pH. Due to its crucial role in anthocyanin production it has been intensively studied in various plants 5,7,8 . Apart from that its transcriptional regulation has also been documented in several studies 6,9 , recently even in Arabidopsis thaliana 10 .…”