Abstract
The non-autonomous Tpn1-related transposons belonging to the CACTA superfamily are the most common spontaneous mutagens in the Japanese morning glory. We have characterized eight spontaneous mutants having Tpn1-related transposons inserted into the ANS gene encording anthocyanidin synthase for anthocyanin biosynthesis. One of them displaying white flowers with variegated red spots and sectors carries 6.4 kb Tpn9 in a unique ANS intron, and the ANS transcripts terminate within Tpn9. The flower variegation is due to somatic excision of Tpn9 from the ANS gene. The seven remaining mutants contain 6.6 kb Tpn8 at the same site of the promoter of the ANS gene, and the Tpn8 insertion suppresses the expression of the ANS gene. The flower pigmentation phenotypes of these mutants vary form snow white to palely colored, and one of them blooms white flowers with marginally pigmented. We will discuss the flower pigmentation of these mutants.
