Poster: Mechanisms of Gene Regulation
P36002: IbMYB1, a regulator of anthocyanin biosynthesis in tuberous root of purple-fleshed sweet potato
Mano, Hironori Contact Presenter||Authors||Mano, Hironori (A) Sato, Kazuhito (B) Higo, Hiromi (B) Minobe, Yuzo (B) |
(A): Plant Genome Center Co., Ltd, Genetic Engineering|
(B): Plant Genome Center Co., Ltd,
A purple-fleshed sweet potato (Ipomoea batatas [L.] Lam.) cultivar Ayamurasaki accumulate a large amount of anthocyanins in the tuberous roots, which are used for safety edible dye production. We isolated MYB genes IbMYB1 and IbMYB2s from Ayamurasaki and found that the IbMYB1gene expressed predominantly in purple-fleshed tuberous roots. The results of transient and stable transformation experiments indicated that expression of IbMYB1 alone was sufficient for induction of all structural anthocyanin genes and anthocyanin accumulation in the flesh of tuberous roots, as well as in heterologous tissues or heterologous plant species. Many transcriptional factors harboring the R2R3-MYB domain, bHLH (basic helix-loop-helix) domain, or WD40 repeats have been identified in various plant species as regulators of flavonoid biosynthesis in flowers, seeds, and fruits. However, the regulatory elements of flavonoid biosynthesis in underground organs have not yet been elucidated. Phylogenic analysis indicated the IbMYB1gene belongs to the same group with other regulators that are responsible for flavonoid synthesis in flowers, seeds, and fruits. On the other hand, a MYB gene express in the roots of morning glory (Ipomoea nil) are more closely related to IbMYB1 than to the other MYB gene express in flowers of morning glory. These results may indicate that the MYB genes working in different tissues were divided before the division of morning glory and sweet potato.