caa a22 4500 606207961 CHVBK 20210128101020.0 cr unu---uuuuu 210128e20150901xx s 000 0 eng 10.1007/s00425-015-2363-8 doi (NATIONALLICENCE)springer-10.1007/s00425-015-2363-8 Metabolic and molecular analyses of white mutant Vaccinium berries show down-regulation of MYBPA1-type R2R3 MYB regulatory factor [Elektronische Daten] [Anja Primetta, Katja Karppinen, Kaisu Riihinen, Laura Jaakola] Main conclusion : MYBPA1-type R2R3 MYB transcription factor shows down-regulation in white mutant berries of Vaccinium uliginosum deficient in anthocyanins but not proanthocyanidins suggesting a role in the regulation of anthocyanin biosynthesis. Berries of the genus Vaccinium are among the best natural sources of flavonoids. In this study, the expression of structural and regulatory flavonoid biosynthetic genes and the accumulation of flavonoids in white mutant and blue-colored wild-type bog bilberry (V. uliginosum) fruits were measured at different stages of berry development. In contrast to high contents of anthocyanins in ripe blue-colored berries, only traces were detected by HPLC-ESI-MS in ripe white mutant berries. However, similar profile and high levels of flavonol glycosides and proanthocyanidins were quantified in both ripe white and ripe wild-type berries. Analysis with qRT-PCR showed strong down-regulation of structural genes chalcone synthase (VuCHS), dihydroflavonol 4-reductase (VuDFR) and anthocyanidin synthase (VuANS) as well as MYBPA1-type transcription factor VuMYBPA1 in white berries during ripening compared to wild-type berries. The profiles of transcript accumulation of chalcone isomerase (VuCHI), anthocyanidin reductase (VuANR), leucoanthocyanidin reductase (VuLAR) and flavonoid 3′5′ hydroxylase (VuF3′5′H) were more similar between the white and the wild-type berries during fruit development, while expression of UDP-glucose: flavonoid 3-O-glucosyltransferase (VuUFGT) showed similar trend but fourfold lower level in white mutant. VuMYBPA1, the R2R3 MYB family member, is a homologue of VmMYB2 of V. myrtillus and VcMYBPA1 of V. corymbosum and belongs to MYBPA1-type MYB family which members are shown in some species to be related with proanthocyanidin biosynthesis in fruits. Our results combined with earlier data of the role of VmMYB2 in white mutant berries of V. myrtillus suggest that the regulation of anthocyanin biosynthesis in Vaccinium species could differ from other species studied. Springer-Verlag Berlin Heidelberg, 2015 Anthocyanins nationallicence Bog bilberry nationallicence Flavonoids nationallicence Fruits nationallicence MYB transcription factors nationallicence Proanthocyanidins nationallicence Vaccinium uliginosum L nationallicence ANR : Anthocyanidin reductase nationallicence ANS : Anthocyanidin synthase nationallicence CHI : Chalcone isomerase nationallicence CHS : Chalcone synthase nationallicence DFR : Dihydroflavonol 4-reductase nationallicence F3′5′H : Flavonoid 3′5′ hydroxylase nationallicence LAR : Leucoanthocyanidin reductase nationallicence UFGT : UDP-glucose: flavonoid 3-O-glucosyltransferase nationallicence Primetta Anja Department of Environmental Science, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland aut Karppinen Katja Genetics and Physiology Unit, University of Oulu, P.O. Box 3000, 90014, Oulu, Finland aut Riihinen Kaisu Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland aut Jaakola Laura Climate Laboratory Holt, Department of Arctic and Marine Biology, UiT the Arctic University of Norway, NO-9037, Tromsø, Norway aut Planta Springer Berlin Heidelberg 242/3(2015-09-01), 631-643 0032-0935 242:3<631 2015 242 425 https://doi.org/10.1007/s00425-015-2363-8 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/s00425-015-2363-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Primetta Anja Department of Environmental Science, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland aut NATIONALLICENCE 700 1- Karppinen Katja Genetics and Physiology Unit, University of Oulu, P.O. Box 3000, 90014, Oulu, Finland aut NATIONALLICENCE 700 1- Riihinen Kaisu Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland aut NATIONALLICENCE 700 1- Jaakola Laura Climate Laboratory Holt, Department of Arctic and Marine Biology, UiT the Arctic University of Norway, NO-9037, Tromsø, Norway aut NATIONALLICENCE 773 0- Planta Springer Berlin Heidelberg 242/3(2015-09-01), 631-643 0032-0935 242:3<631 2015 242 425