polymorphisms (SNPs), which are defined by
whole-genome sequencing of accessions, are
available (Huang et al. 2010 ; Han and Huang
2013 ). Based on a sufficient density of SNPs (a few
SNPs per gene) in a few hundred accessions, a
genome-wide association study (GWAS) could be
conducted. Metabolome GWAS (mGWAS) will
dramatically improve the annotation of genes and
metabolites (Adamski and Suhre 2013 ). mGWAS
analysis inL. japonicuswill promote the meta-
bolic breeding of leguminous crops. In the course
of these activities, an integrated metabolomics
database will be developed, and databases and data
resources will be standardized as a practical met-
abolomics platform for mining biological discov-
eries (Fig.16.2).
16.7 Conclusions
This chapter outlines recent advances in plant
metabolomics with case studies ofL. japonicus
and poses the next challenges for integrated
metabolomics. It is desirable that these activities
will become general and conventional practice in
model and non-model plants. The public data of
L. japonicus metabolomics will be especially
useful in many studies of leguminous crops of
economic importance.
Acknowledgments This work was supported by the
RIKEN Plant Science Center, Japan Science and Tech-
nology Agency (CREST grant), Japan Advanced Plant
Science Research Network and Fuji Foundation for Pro-
tein Research. RILs were distributed by the National
BioResource Project (Legume Base). We thank Dr. Ryo
Nakabayashi (RIKEN), Mrs. Makoto Suzuki (RIKEN),
Akane Sakata (RIKEN), Yutaka Yamada (RIKEN),
Tetsuya Mori (RIKEN) and Muneo Sato (JST GRENE
NC-CARP) for their useful comments and LC-MS/MS
analysis of the metabolomics technologies.
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