RRC ID 56892
Author Hoshino A, Mizuno T, Shimizu K, Mori S, Fukada-Tanaka S, Furukawa K, Ishiguro K, Tanaka Y, Iida S.
Title Generation of Yellow Flowers of the Japanese Morning Glory by Engineering Its Flavonoid Biosynthetic Pathway toward Aurones.
Journal Plant Cell Physiol
Abstract Wild-type plants of the Japanese morning glory (Ipomoea nil) produce blue flowers that accumulate anthocyanin pigments, whereas its mutant cultivars show wide range flower color such as red, magenta and white. However, I. nil lacks yellow color varieties even though yellow flowers were curiously described in words and woodblocks printed in the 19th century. Such yellow flowers have been regarded as 'phantom morning glories', and their production has not been achieved despite efforts by breeders of I. nil. The chalcone isomerase (CHI) mutants (including line 54Y) bloom very pale yellow or cream-colored flowers conferred by the accumulation of 2', 4', 6', 4-tetrahydoroxychalcone (THC) 2'-O-glucoside. To produce yellow phantom morning glories, we introduced two snapdragon (Antirrhinum majus) genes to the 54Y line by encoding aureusidin synthase (AmAS1) and chalcone 4'-O-glucosyltransferase (Am4'CGT), which are necessary for the accumulation of aureusidin 6-O-glucoside and yellow coloration in A. majus. The transgenic plants expressing both genes exhibit yellow flowers, a character sought for many years. The flower petals of the transgenic plants contained aureusidin 6-O-glucoside, as well as a reduced amount of THC 2'-O-glucoside. In addition, we identified a novel aurone compound, aureusidin 6-O-(6″-O-malonyl)-glucoside, in the yellow petals. A combination of the coexpression of AmAS1 and Am4'CGT and suppression of CHI is an effective strategy for generating yellow varieties in horticultural plants.
Volume 60(8)
Pages 1871-1879
Published 2019-8-1
DOI 10.1093/pcp/pcz101
PII 5499181
PMID 31135027
MeSH Benzofurans / metabolism* Flavonoids / metabolism* Flowers / metabolism* Gene Expression Regulation, Plant Ipomoea nil / metabolism* Metabolic Engineering / methods* Signal Transduction / physiology
IF 3.929
Times Cited 0
Morning Glory AK29