caa a22 4500 60620802X CHVBK 20210128101020.0 cr unu---uuuuu 210128e20150901xx s 000 0 eng 10.1007/s00425-015-2365-6 doi (NATIONALLICENCE)springer-10.1007/s00425-015-2365-6 Tobacco streak virus (strain dahlia) suppresses post-transcriptional gene silencing of flavone synthase II in black dahlia cultivars and causes a drastic flower color change [Elektronische Daten] [Ayumi Deguchi, Fumi Tatsuzawa, Munetaka Hosokawa, Motoaki Doi, Sho Ohno] Main conclusion : Tobacco streak virus suppressed post-transcriptional gene silencing and caused a flower color change in black dahlias, which supported the role of cyanidin-based anthocyanins for black flower appearance. Black flower color of dahlia (Dahlia variabilis) has been attributed, in part, to the high accumulation of cyanidin-based anthocyanins that occurs when flavone synthesis is reduced because of post-transcriptional genesilencing (PTGS) of flavone synthase II (DvFNS). There are also purple-flowering plants that have emerged from a black cultivar ‘Kokucho'. We report that the purple color is not caused by a mutation, as previously thought, but by infection with tobacco streak virus (TSVdahlia), which suppresses the PTGS of DvFNS. When TSVdahlia was eliminated from the purple-flowering ‘Kokucho' by leaf primordia-free shoot apical meristem culture, the resulting flowers were black. TSVdahlia-infected purple flowers had lower numbers of siRNAs to DvFNS than black flowers, suggesting that TSVdahlia has a silencing suppressor. The graft inoculation of other black cultivars with TSVdahlia altered their flower color drastically except for ‘Fidalgo Blacky', a very deep black cultivar with the highest amount of cyanidin-based anthocyanins. The flowers of all six TSVdahlia-infected cultivars accumulated increased amounts of flavones and reduced amounts of cyanidin-based anthocyanins. ‘Fidalgo Blacky' remained black despite the change in pigment accumulation, and the amounts of cyanidin-based anthocyanins in its TSVdahlia-infected plants were still higher than those of other cultivars. We propose that black flower color in dahlia is controlled by two different mechanisms that increase the amount of cyanidin-based anthocyanins: DvFNS PTGS-dependent and -independent mechanisms. If both mechanisms occur simultaneously, the flower color will be blacker than if only a single mechanism is active. Springer-Verlag Berlin Heidelberg, 2015 Cyanidin nationallicence Dahlia variabilis nationallicence FNS II nationallicence PTGS nationallicence Silencing suppressor nationallicence ANS : Anthocyanidin synthase nationallicence AV-2 : Asparagus virus 2 nationallicence bHLH : Basic helix-loop-helix nationallicence CHI : Chalcone isomerase nationallicence CHS : Chalcone synthase nationallicence CMV : Cucumber mosaic virus nationallicence CP : Coat protein nationallicence CSVd : Chrysanthemum stunt viroid nationallicence DFR : Dihydroflavonol 4-reductase nationallicence DMV : Dahlia mosaic virus nationallicence F3H : Flavanone 3-hydroxylase nationallicence F3′H : Flavonoid 3′-hydroxylase nationallicence FNS II : Flavone synthase II nationallicence HPLC : High performance liquid chromatography nationallicence INSV : Impatiens necrotic spot virus nationallicence LP-free SAM : Leafprimordia-free shoot apical meristem nationallicence MP : Movement protein nationallicence PTGS : Post-transcriptional gene silencing nationallicence PSTVd : Potato spindle tuber viroid nationallicence RT-PCR : Reverse transcription-PCR nationallicence siRNA : Small interfering RNA nationallicence TSV : Tobacco streak virus nationallicence TSWV : Tomato spotted wilt virus nationallicence Deguchi Ayumi Laboratory of Vegetable and Ornamental Horticulture, Graduate School of Agriculture, Kyoto University, Sakyo-ku, 606-8502, Kyoto, Japan aut Tatsuzawa Fumi Faculty of Agriculture, Iwate University, 020-8550, Morioka, Japan aut Hosokawa Munetaka Laboratory of Vegetable and Ornamental Horticulture, Graduate School of Agriculture, Kyoto University, Sakyo-ku, 606-8502, Kyoto, Japan aut Doi Motoaki Laboratory of Vegetable and Ornamental Horticulture, Graduate School of Agriculture, Kyoto University, Sakyo-ku, 606-8502, Kyoto, Japan aut Ohno Sho Laboratory of Vegetable and Ornamental Horticulture, Graduate School of Agriculture, Kyoto University, Sakyo-ku, 606-8502, Kyoto, Japan aut Planta Springer Berlin Heidelberg 242/3(2015-09-01), 663-675 0032-0935 242:3<663 2015 242 425 https://doi.org/10.1007/s00425-015-2365-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00425-015-2365-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Deguchi Ayumi Laboratory of Vegetable and Ornamental Horticulture, Graduate School of Agriculture, Kyoto University, Sakyo-ku, 606-8502, Kyoto, Japan aut NATIONALLICENCE 700 1- Tatsuzawa Fumi Faculty of Agriculture, Iwate University, 020-8550, Morioka, Japan aut NATIONALLICENCE 700 1- Hosokawa Munetaka Laboratory of Vegetable and Ornamental Horticulture, Graduate School of Agriculture, Kyoto University, Sakyo-ku, 606-8502, Kyoto, Japan aut NATIONALLICENCE 700 1- Doi Motoaki Laboratory of Vegetable and Ornamental Horticulture, Graduate School of Agriculture, Kyoto University, Sakyo-ku, 606-8502, Kyoto, Japan aut NATIONALLICENCE 700 1- Ohno Sho Laboratory of Vegetable and Ornamental Horticulture, Graduate School of Agriculture, Kyoto University, Sakyo-ku, 606-8502, Kyoto, Japan aut NATIONALLICENCE 773 0- Planta Springer Berlin Heidelberg 242/3(2015-09-01), 663-675 0032-0935 242:3<663 2015 242 425