A chalcone isomerase-like protein enhances flavonoid production and flower pigmentation

Yasumasa Morita, Kyoko Takagi, Masako Fukuchi-Mizutani, Kanako Ishiguro, Yoshikazu Tanaka, Eiji Nitasaka, Masayoshi Nakayama, Norio Saito, Takashi Kagami, Atsushi Hoshino, Shigeru Iida

Research output: Contribution to journalArticlepeer-review

96 Citations (Scopus)


Flavonoids are major pigments in plants, and their biosynthetic pathway is one of the best-studied metabolic pathways. Here we have identified three mutations within a gene that result in pale-colored flowers in the Japanese morning glory (Ipomoea nil). As the mutations lead to a reduction of the colorless flavonoid compound flavonol as well as of anthocyanins in the flower petal, the identified gene was designated enhancer of flavonoid production (EFP). EFP encodes a chalcone isomerase (CHI)-related protein classified as a type IV CHI protein. CHI is the second committed enzyme of the flavonoid biosynthetic pathway, but type IV CHI proteins are thought to lack CHI enzymatic activity, and their functions remain unknown. The spatio-temporal expression of EFP and structural genes encoding enzymes that produce flavonoids is very similar. Expression of both EFP and the structural genes is coordinately promoted by genes encoding R2R3-MYB and WD40 family proteins. The EFP gene is widely distributed in land plants, and RNAi knockdown mutants of the EFP homologs in petunia (Petunia hybrida) and torenia (Torenia hybrida) had pale-colored flowers and low amounts of anthocyanins. The flavonol and flavone contents in the knockdown petunia and torenia flowers, respectively, were also significantly decreased, suggesting that the EFP protein contributes in early step(s) of the flavonoid biosynthetic pathway to ensure production of flavonoid compounds. From these results, we conclude that EFP is an enhancer of flavonoid production and flower pigmentation, and its function is conserved among diverse land plant species.

Original languageEnglish
Pages (from-to)294-304
Number of pages11
JournalPlant Journal
Issue number2
Publication statusPublished - Apr 2014

All Science Journal Classification (ASJC) codes

  • Genetics
  • Plant Science
  • Cell Biology


Dive into the research topics of 'A chalcone isomerase-like protein enhances flavonoid production and flower pigmentation'. Together they form a unique fingerprint.

Cite this