Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: March 15, 2007
Publication Date: June 27, 2007
Citation: Ma, H., Griesbach, R.J., and Pooler, M.R. 2007. Studies of anthocyanin regulatory genes in Phalaenopsis using a transient expression system. HortScience. 42:971(abstract). Technical Abstract: Anthocyanins are one of the primary color-producing compounds in plants, and their expression is controlled by a complex pathway of regulatory genes and transcription factors. Plant pigmentation, especially in leaves and flowers, is especially important in ornamental plants, where novel colors often drive the market for new plants. Our lab is investigating methods to change or enhance flower or foliage color in ornamental plants using both traditional breeding and genetic engineering. In order to test gene constructs and the effects of various regulatory genes on transgenic anthocyanin expression, we developed a normalized transient expression system based on particle bombardment of white Phalaenopsis petals that uses GFP gene expression as an internal control. Using this system, we confirmed that the albescent phenotype (white petals, colored labellum) in Phalaenopsis amabilis could be complemented by transient expression of maize Lc (myc) and C1 (myb) regulatory genes. In addition, the ratio of these regulatory genes was critical in anthocyanin expression in that detectable anthocyanin accumulation only occurred with with high levels of C1 regardless of the Lc expression level. We are currently examining how these and other regulatory and helper component proteins affect gene expression so that we can develop ornamental germplasm with novel pigmentation.