|Yuan, Youxi - Cornell University - New York|
|Chiu, Li-wei - Cornell University - New York|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/10/2009
Publication Date: 4/10/2009
Citation: Yuan, Y., Chiu, L., Li, L. 2009. Regulation of anthocyanin biosynthesis in red cabbages [abstract]. Plant Biology 2009 Meeting.
Technical Abstract: The color of red cabbage is due to the accumulation of large quantity of anthocyanins. To investigate the general regulatory control of anthocyanin production in red cabbages, the expression of anthocyanin biosynthetic genes and regulators from eight commercial cultivars was examined. While the four green varieties had negligible amounts of anthocyanins under normal growth condition, the four red varieties contained varied amounts of anthocyanins to levels up to 1.60 mg g-1 fresh weight. HPLC analysis of the four red varieties revealed that they produced similar composition of various forms of cyanidin glucosides, but at different concentration. Molecular analysis indicated that all the red cabbages shared common pattern of regulatory control for the anthocyanin biosynthesis. While the early genes (from PAL to F3H) of anthocyanin biosynthetic pathway showed similar expression levels between green and red cultivars, the late structural genes, F3’H, DFR, LDOX, UGT and GST, were constitutively up-regulated during all the developmental stages of red varieties. The expression of these structural genes also dramatically increased in green and red cabbages under nutrient stresses. The increased expression of the late structural genes coincided with a coordinated increase in transcript levels of a bHLH gene BoTT8 and a MYB transcription factor BoPAP1. These results indicate that the activation of two regulatory factors by unknown mechanisms up-regulates all the late structural genes for the onset of anthocyanin biosynthesis in the red cabbages. Moreover, the amount of total anthocyanins in red cabbages was found to be positively correlated with total antioxidant power, implicating the potential health benefit of red cabbages to human health.