RRC ID 4664
Author Kai K, Wakasa K, Miyagawa H.
Title Metabolism of indole-3-acetic acid in rice: identification and characterization of N-beta-D-glucopyranosyl indole-3-acetic acid and its conjugates.
Journal Phytochemistry
Abstract A search was made for conjugates of indole-3-acetic acid (IAA) in rice (Oryza sativa) using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) in order to elucidate unknown metabolic pathways for IAA. N-beta-d-Glucopyranosyl indole-3-acetic acid (IAA-N-Glc) was found in an alkaline hydrolysate of rice extract. A quantitative analysis of 3-week-old rice demonstrated that the total amount of IAA-N-Glc was equal to that of IAA. A LC-ESI-MS/MS-based analysis established that the major part of IAA-N-Glc was present as bound forms with aspartate and glutamate. Their levels were in good agreement with the total amount of IAA-N-Glc during the vegetative growth of rice. Further detailed analysis showed that both conjugates highly accumulated in the root. The free form of IAA-N-Glc accounted for 60% of the total in seeds but could not be detected in the vegetative tissue. An incorporation study using deuterium-labeled compounds showed that the amino acid conjugates of IAA-N-Glc were biosynthesized from IAA-amino acids. IAA-N-Glc and/or its conjugates were also found in extracts of Arabidopsis, Lotus japonicus, and maize, suggesting that N-glucosylation of indole can be the common metabolic pathway of IAA in plants.
Volume 68(20)
Pages 2512-22
Published 2007-10
DOI 10.1016/j.phytochem.2007.05.040
PII S0031-9422(07)00344-5
PMID 17628621
MeSH Amides / metabolism Aspartic Acid / metabolism Chromatography, Liquid Glutamic Acid / metabolism Indoleacetic Acids / metabolism* Indoles* / chemical synthesis Indoles* / isolation & purification Monosaccharides* / biosynthesis Monosaccharides* / chemical synthesis Monosaccharides* / isolation & purification Oryza / growth & development Oryza / metabolism* Plant Extracts / chemistry Plant Roots / growth & development Plant Roots / metabolism Plant Shoots / growth & development Plant Shoots / metabolism Spectrometry, Mass, Electrospray Ionization Tandem Mass Spectrometry
IF 2.905
Times Cited 7
Lotus / Glycine Gifu B-129