Systematic approaches to using the FOX hunting system to identify useful rice genes.
Ectopic gene expression, or the gain-of-function approach, has the advantage that once the function of a gene is known the gene can be transferred to many different plants by transformation. We previously reported a method, called FOX hunting, that involves ectopic expression of Arabidopsis full-length cDNAs in Arabidopsis to systematically generate gain-of-function mutants. This technology is most beneficial for generating a heterologous gene resource for analysis of useful plant gene functions. As an initial model we generated more than 23,000 independent Arabidopsis transgenic lines that expressed rice fl-cDNAs (Rice FOX Arabidopsis lines). The short generation time and rapid and efficient transformation frequency of Arabidopsis enabled the functions of the rice genes to be analyzed rapidly. We screened rice FOX Arabidopsis lines for alterations in morphology, photosynthesis, element accumulation, pigment accumulation, hormone profiles, secondary metabolites, pathogen resistance, salt tolerance, UV signaling, high light tolerance, and heat stress tolerance. Some of the mutant phenotypes displayed by rice FOX Arabidopsis lines resulted from the expression of rice genes that had no homologs in Arabidopsis. This result demonstrated that rice fl-cDNAs could be used to introduce new gene functions in Arabidopsis. Furthermore, these findings showed that rice gene function could be analyzed by employing Arabidopsis as a heterologous host. This technology provides a framework for the analysis of plant gene function in a heterologous host and of plant improvement by using heterologous gene resources.
Kondou
Youichi
Y
RIKEN Plant Science Center, Yokohama, Kanagawa, Japan.
Higuchi
Mieko
M
Takahashi
Shinya
S
Sakurai
Tetsuya
T
Ichikawa
Takanari
T
Kuroda
Hirofumi
H
Yoshizumi
Takeshi
T
Tsumoto
Yuko
Y
Horii
Yoko
Y
Kawashima
Mika
M
Hasegawa
Yukako
Y
Kuriyama
Tomoko
T
Matsui
Keiko
K
Kusano
Miyako
M
Albinsky
Doris
D
Takahashi
Hideki
H
Nakamura
Yukiko
Y
Suzuki
Makoto
M
Sakakibara
Hitoshi
H
Kojima
Mikiko
M
Akiyama
Kenji
K
Kurotani
Atsushi
A
Seki
Motoaki
M
Fujita
Miki
M
Enju
Akiko
A
Yokotani
Naoki
N
Saitou
Tsutomu
T
Ashidate
Kozue
K
Fujimoto
Naka
N
Ishikawa
Yasuo
Y
Mori
Yayoi
Y
Nanba
Rie
R
Takata
Kazumasa
K
Uno
Kuniko
K
Sugano
Shoji
S
Natsuki
Jun
J
Dubouzet
Joseph Gogo
JG
Maeda
Satoru
S
Ohtake
Miki
M
Mori
Masaki
M
Oda
Kenji
K
Takatsuji
Hiroshi
H
Hirochika
Hirohiko
H
Matsui
Minami
M
D017360:Arabidopsis / Q000378:metabolism; D001482:Base Composition; D018076:DNA, Complementary / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D020869:Gene Expression Profiling / Q000379:methods*; D017343:Genes, Plant; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D030821:Plants, Genetically Modified / Q000378:metabolism
D018076:DNA, Complementary; D018744:DNA, Plant