Molecular characterization of an anthocyanin-related glutathione -transferase gene in cyclamen

Kitamura, Satoshi; Akita, Yusuke; Ishizaka, Hiroshi*; Narumi, Issei; Tanaka, Atsushi

In order to identify the anthocyanin-related GST in cyclamen, four candidates of GSTs (CkmGST1 to CkmGST4) were isolated. Phylogenetic analysis indicated that CkmGST3 was closely related to PhAN9, an anthocyanin-related GST of petunia. Expression analysis at different developmental stages of petals revealed that CkmGST3 was strongly expressed in paler pigmented petals than in fully pigmented petals, in contrast to the constitutive expression of the other three candidates during petal development. This expression pattern of CkmGST3 was correlated with those of other anthocyaninbiosynthetic genes such as CkmF3'5'H and CkmDFR2. Molecular complementation of Arabidopsis , a knockout mutant of an anthocyanin-related GST gene, demonstrated that CkmGST3 could complement the anthocyanin-less phenotype of . Transgenic plants that expressed the other three CkmGSTs did not show anthocyanin accumulation. These results indicate CkmGST3 functions in anthocyanin accumulation in cyclamen.