Chalcone 3- Hydroxylase: yellow colouration of flowers
The novel method to form structured chromium layers uses electroplating at constant current density and initiates structure formation through temperature changes. Other than state of the art pulse electroplating, this method minimizes additives, energy consumption and risks. Structured chromium
layers produced with the novel method have improved properties. They are very hard and wear resistant like conventional hard chrome. Depending on the parameters of the deposition process their surface topography can be adjusted for repellent - “easy to clean” properties – or vice versa for fluid
retention properties as well, properties most needed in functional coatings like media contact surfaces.
Different yellow pigments can be responsible for the yellow colouration of flowers. This includes the wide-spread carotenoids, but also betalains, quinones, yellow flavonoids and anthochlore pigments (chalcones and aurones). Many popular ornamental plants do not produce yellow varieties or only ivory and pale yellow varieties despite of intensive conventional breeding efforts.
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World-wide, there are many attempts to use molecular breeding approaches for the creation of yellow varieties of such ornamental
plants. Currently, two approaches are performed; one using aureusidine
synthase (AUS) from snapdragon, the others chalcone reductase (CHR)
present e.g. in soybean for the accumulation of stable 6’-deoxychalcones.
However, there are no reports available on the creation of prototypes
showing a satisfying yellow flower colour.
According to the invention it was found out that polypeptides, in particular
hydroxylases, as for example flavonoid 3’-hydroxylases, are able to
hydroxylate chalcones at position 3. The knowledge of such hydroxylases
enables the modulation of the expression of these hydroxylases in order to, for example, overexpress or inhibit these in vivo. In particular, the knowledge of these enzymes enables the modulation of the quantity of hydroxylated chalcones in a plant or plant cell, respectively, in order to thus change the colour composition in the latter. Thus, plants, which comprise the nucleic acid molecules according to the invention, have, for example, flowers with an
intensive yellow colouration.
- Intensification of the yellow colouration due to the enrichment of chalcones with a 3,4-hydroxy pattern
- Increased formation of aurones
This invention may be used for the creation of yellow flower colour in species which do not naturally produce yellow varieties. Possible target plants could be e.g.fuchsia, cyclamen, poinsettia, petunia, African violet, azalea, Easter lily, and geranium. Although pale yellow or ivory varieties of a few of these
species exist, the availability of intensive yellow varieties would be a novel and interesting market input.
Stichwortechalcone 3-hydroxylase, molecular breeding , yellow flower colour