TY - JOUR
T1 - Isolation of WDR and bHLH genes related to flavonoid synthesis in grapevine (Vitis vinifera L.)
AU - Matus, J. T.
AU - Poupin, M. J.
AU - Cañón, P.
AU - Bordeu, E.
AU - Alcalde, J. A.
AU - Arce-Johnson, P.
N1 - Funding Information:
Acknowledgments We wish to thank Uely Grossniklaus (University of Zurich, SZ) for the p207-DONOR and pMDC84 GFP-fusion vectors, and Paula Salinas and Dave Jackson (Cold Spring Harbour Laboratory, NY) for their guidance on GFP visualization in tobacco and onion cells, respectively. Special thanks to Agnès Ageorges and Nancy Terrier (INRA Montpellier) for sharing bHLH and WDR QPCR primers. This work was supported by the Chilean Wine Consortium 05CTE01-03, the Fruit Consortium, 07Genoma01, Millennium Nucleus for Plant Functional Genomics (P06-009-F), FONDECYT 1100709, and by fellowships awarded to JTM (MECESUP and CONICYT AT24060171) and MJP (CONICYT). Finally, we thank Nancy Terrier and Michael Handford for critically reading the manuscript.
PY - 2010
Y1 - 2010
N2 - Anthocyanins and tannins are two of the most abundant flavonoids found in grapevine, and their synthesis is derived from the phenylpropanoid pathway. As described for model species such as Arabidopsis thaliana, maize and petunia, the end-point branches of this pathway are tightly regulated by the combinatorial interaction of three families of regulatory factors; MYB, bHLH (also known as MYC) and WDR proteins. Among these, only MYB genes have been previously identified in grapes. Here, we report the isolation of the first members from the WDR and bHLH families found in Vitis vinifera, named WDR1, WDR2 and MYCA1. WDR1 contributed positively to the accumulation of anthocyanins when it was overexpressed in A. thaliana, although it was not possible to determine the function of WDR2 by ectopic expression. The sub-cellular localizations of WDR1 and MYCA1 were observed by means of GFPfusion proteins, indicating both cytoplasm and nuclear localization, in contrast to the localization of a MYB factor exclusively in the nucleus. The expression patterns of these genes were quantified in coloured reproductive organs throughout development, and correlated with anthocyanin accumulation and the expression profiles of the flavonoidrelated MYBA1-2, UFGT, and ANR genes. In vitro grapevine plantlets grown under high salt concentrations showed a cultivar-dependent response for anthocyanin accumulation, which correlated with the expression of MYBA1-2, MYCA1 and WDR1 genes. These results suggest that MYCA1 may regulate ANR and UFGT and that this last control is easier to distinguish whenever MYBA genes are absent or in low abundance. Future studies should address the specific interactions of these proteins and their quantitative contribution to flavonoid synthesis in grape berries.
AB - Anthocyanins and tannins are two of the most abundant flavonoids found in grapevine, and their synthesis is derived from the phenylpropanoid pathway. As described for model species such as Arabidopsis thaliana, maize and petunia, the end-point branches of this pathway are tightly regulated by the combinatorial interaction of three families of regulatory factors; MYB, bHLH (also known as MYC) and WDR proteins. Among these, only MYB genes have been previously identified in grapes. Here, we report the isolation of the first members from the WDR and bHLH families found in Vitis vinifera, named WDR1, WDR2 and MYCA1. WDR1 contributed positively to the accumulation of anthocyanins when it was overexpressed in A. thaliana, although it was not possible to determine the function of WDR2 by ectopic expression. The sub-cellular localizations of WDR1 and MYCA1 were observed by means of GFPfusion proteins, indicating both cytoplasm and nuclear localization, in contrast to the localization of a MYB factor exclusively in the nucleus. The expression patterns of these genes were quantified in coloured reproductive organs throughout development, and correlated with anthocyanin accumulation and the expression profiles of the flavonoidrelated MYBA1-2, UFGT, and ANR genes. In vitro grapevine plantlets grown under high salt concentrations showed a cultivar-dependent response for anthocyanin accumulation, which correlated with the expression of MYBA1-2, MYCA1 and WDR1 genes. These results suggest that MYCA1 may regulate ANR and UFGT and that this last control is easier to distinguish whenever MYBA genes are absent or in low abundance. Future studies should address the specific interactions of these proteins and their quantitative contribution to flavonoid synthesis in grape berries.
KW - Anthocyanins
KW - MYB4a
KW - MYBA1
KW - Pigmentation
KW - TT8
KW - TTG1
KW - WD40
UR - http://www.scopus.com/inward/record.url?scp=77954500670&partnerID=8YFLogxK
U2 - 10.1007/s11103-010-9597-4
DO - 10.1007/s11103-010-9597-4
M3 - Article
C2 - 20112051
AN - SCOPUS:77954500670
VL - 72
SP - 607
EP - 620
JO - Plant Molecular Biology
JF - Plant Molecular Biology
SN - 0167-4412
IS - 6
ER -