
Functional analysis of soybean genes involved in flavonoid biosynthesis by virus‐induced gene silencing
Author(s) -
Nagamatsu Atsushi,
Masuta Chikara,
Senda Mineo,
Matsuura Hideyuki,
Kasai Atsushi,
Hong JinSung,
Kitamura Keisuke,
Abe Jun,
Kanazawa Akira
Publication year - 2007
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/j.1467-7652.2007.00288.x
Subject(s) - biology , chalcone synthase , gene , gene silencing , orfs , gene expression , flavonoid biosynthesis , flavonoid , kaempferol , citrus tristeza virus , anthocyanin , virus , genetics , plant virus , biochemistry , botany , transcriptome , peptide sequence , open reading frame , antioxidant
Summary Virus‐induced gene silencing (VIGS) is a powerful tool for functional analysis of genes in plants. A wide‐host‐range VIGS vector, which was developed based on the Cucumber mosaic virus (CMV), was tested for its ability to silence endogenous genes involved in flavonoid biosynthesis in soybean. Symptomless infection was established using a pseudorecombinant virus, which enabled detection of specific changes in metabolite content by VIGS. It has been demonstrated that the yellow seed coat phenotype of various cultivated soybean lines that lack anthocyanin pigmentation is induced by natural degradation of chalcone synthase ( CHS ) mRNA. When soybean plants with brown seed coats were infected with a virus that contains the CHS gene sequence, the colour of the seed coats changed to yellow, which indicates that the naturally occurring RNA silencing is reproduced by VIGS. In addition, CHS VIGS consequently led to a decrease in isoflavone content in seeds. VIGS was also tested on the putative flavonoid 3′‐hydroxylase ( F3′H ) gene in the pathway. This experiment resulted in a decrease in the content of quercetin relative to kaempferol in the upper leaves after viral infection, which suggests that the putative gene actually encodes the F3′H protein. In both experiments, a marked decrease in the target mRNA and accumulation of short interfering RNAs were detected, indicating that sequence‐specific mRNA degradation was induced. The present report is a successful demonstration of the application of VIGS for genes involved in flavonoid biosynthesis in plants; the CMV‐based VIGS system provides an efficient tool for functional analysis of soybean genes.