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Bread wheat producing grain in which the pericarp is purple is considered to be a useful source of dietary anthocyanins. The trait is under the control of the Pp-1 homoealleles (mapping to each of the group 7 chromosomes) and Pp3 (on chromosome 2A). Here, TaMyc1 was identified as a likely candidate for Pp3. The gene encodes a MYC-like transcription factor. In genotypes carrying the dominant Pp3 allele, TaMyc1 was strongly transcribed in the pericarp and, although at a lower level, also in the coleoptile, culm and leaf. The gene was located to chromosome 2A. Three further copies were identified, one mapping to the same chromosome arm as TaMyc1 and the other two mapping to the two other group 2 chromosomes; however none of these extra copies were transcribed in the pericarp. Analysis of the effect of the presence of combinations of Pp3 and Pp-1 genotype on the transcription behavior of TaMyc1 showed that the dominant allele Pp-D1 suppressed the transcription of TaMyc1. [ABSTRACT FROM AUTHOR]

Near-isogenic line of the common spring wheat cultivar 'Saratovskaya 29', designated 'i:S29 Ra', has been earlier developed during eight backcrosses and selection for the red auricle colour inherited from donor 'Ulyanovka'. In this study, the line 'i:S29 Ra' was characterized using 274 molecular and a number of morphological markers. It was found that the donor's genome material in 'i:S29 Ra' is presented by a fragment on chromosome 7D flanked by the microsatellite loci Xgwm0044 and Xgwm1481 and carrying cluster of the genes Rc-D1 (red coleoptile), Pc-D1 (purple culm), Pls-D1 (purple leaf sheaths), Plb-D1 (purple leaf blades) and Ra-D1 (red auricles), conferring intensive anthocyanin pigmentation of the coleoptile, culm, leaf sheaths, leaf blades and auricles, respectively. The Ra-D1 is a novel locus described in wheat. The relative anthocyanin contents (OD530) in different parts of wheat plant and expression level of the anthocyanin biosynthesis (AB) structural genes in auricles were compared between 'i:S29 Ra' and 'S29'. In auricles of 'i:S29 Ra', the OD530 (optical density) value was twice higher and transcription of some AB structural genes was increased in comparison with 'S29', suggesting regulatory role of the Ra gene in anthocyanin biosynthesis in wheat. [ABSTRACT FROM AUTHOR]