A MOLECULAR MARKER SYSTEM FOR IDENTIFICATION OF THE COLOUR-LOCUS IN DIFFERENT TISSUES OF GRAPEVINE (VITIS VINIFERA L.)
Anthocyanins are red- or purple-coloured secondary metabolites present in many tissues of many plants and are a subgroup of flavonoids. Most grapevine cultivars can be divided in red and white although the colour spectrum goes from white over red and grey to blue and black. Each cultivar has a unique set of antho-cyanins. The composition and their concentration in the berry skin determine colour-variation in grape. The expression of the last gene in the pathway leading to the grape-colour UDP-Glc-Flavonoid-3-O-Glucosyltransferase (UFGT) gene is much lower in white grapes than in red or black and is controlled by transcription-factors VvMYBA1 and VvMYBA2. The two paralogous genes are adjacent, building a single locus inherited with berry colour. The VvMYBA1 gene is not expressed in white berries mainly to an insertion-mutation of Gret1 (Grape retrotransposon 1) in the promoter of VvMYBA1. Based on this locus we used PCR-primers, both published and self designed, to develop an easy-to-use marker system to determine the potential berry skin colour from woody cuttings. With this system most of the cultivars can be distinguished, except Pinot gris and Red Traminer. Since Pinot gris is prone to show colour chimaeras, sometimes white berry mutations or white and grey coloured sectors of berry skin can be seen. The application of the system to different tissues has shown great differences in various tissues like wood, roots, anthers, leaves and grape skin.
Ruh, N., Bleser, E., Rühl, E. and Bitz, O. (2014). A MOLECULAR MARKER SYSTEM FOR IDENTIFICATION OF THE COLOUR-LOCUS IN DIFFERENT TISSUES OF GRAPEVINE (VITIS VINIFERA L.). Acta Hortic. 1046, 477-483
Vvmyba1, UDP-Glc-Flavonoid-3-O-Glucosyltransferase (UFGT), "easy-to-use" marker system