Identification of a Genetic Factor Required for High γ-Isoform Concentration in Rice Vitamin E

Daisuke Sekine, Kazumasa Murata, Toshiyuki Kimura, Kiyotaka Nakagawa, Teruo Miyazawa

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)


The γ-isoforms of tocopherols (Tc) and tocotrienols (T3) possess high biological activities in comparison to the α-isoforms. The concentrations of Tc and T3 isoforms in rice (Oriza sativa) was cultivar-dependent. Using chromosome segment substitution lines (CSSLs) and near isogenic lines (NILs) of indica cultivar "Kasalath" in a japonica cultivar "Koshihikari" genetic background, the Kasalath genomic segment on chromosome 2 was determined to be responsible for the high γ-isoform concentration: γ-tocopherol methyltransferase (γ-TMT) was identified as a candidate gene. An amino acid substitution in the coding region and several nucleotide polymorphisms, including an insertion of 10 base pairs in the promoter region, were identified. Gene expression analysis revealed that low expression levels of the γ-TMT gene in Kasalath were not associated with the γ-isoform concentration. Genetic variations in the coding region of the γ-TMT gene may play a major role in determining the γ-isoform concentration. This information could be used to breed rice with a high γ-isoform content.

Original languageEnglish
Pages (from-to)9368-9373
Number of pages6
JournalJournal of Agricultural and Food Chemistry
Issue number49
Publication statusPublished - 2016 Dec 14


  • breeding
  • isoform biosynthesis
  • rice
  • tocotrienols
  • γ-tocopherol methyltransferase


Dive into the research topics of 'Identification of a Genetic Factor Required for High γ-Isoform Concentration in Rice Vitamin E'. Together they form a unique fingerprint.

Cite this