A genome-wide gain-of function analysis of rice genes using the FOX-hunting system.
The latest report has estimated the number of rice genes to be approximately 32,000. To elucidate the functions of a large population of rice genes and to search efficiently for agriculturally useful genes, we have been taking advantage of the Full-length cDNA Over-eXpresser (FOX) gene-hunting system. This system is very useful for analyzing various gain-of-function phenotypes from large populations of transgenic plants overexpressing cDNAs of interest and others with unknown or important functions. We collected the plasmid DNAs of 13,980 independent full-length cDNA (FL-cDNA) clones to produce a FOX library by placing individual cDNAs under the control of the maize Ubiquitin-1 promoter. The FOX library was transformed into rice by Agrobacterium-mediated high-speed transformation. So far, we have generated approximately 12,000 FOX-rice lines. Genomic PCR analysis indicated that the average number of FL-cDNAs introduced into individual lines was 1.04. Sequencing analysis of the PCR fragments carrying FL-cDNAs from 8615 FOX-rice lines identified FL-cDNAs in 8225 lines, and a database search classified the cDNAs into 5462 independent ones. Approximately 16.6% of FOX-rice lines examined showed altered growth or morphological characteristics. Three super-dwarf mutants overexpressed a novel gibberellin 2-oxidase gene,confirming the importance of this system. We also show here the other morphological alterations caused by individual FL-cDNA expression. These dominant phenotypes should be valuable indicators for gene discovery and functional analysis.
Nakamura
Hidemitsu
H
Division of Genome and Biodiversity Research, NationalInstitute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8602, Japan.
Hakata
Makoto
M
Amano
Kou
K
Miyao
Akio
A
Toki
Naoko
N
Kajikawa
Mariko
M
Pang
Jinhuan
J
Higashi
Naokuni
N
Ando
Shigeko
S
Toki
Seiichi
S
Fujita
Miki
M
Enju
Akiko
A
Seki
Motoaki
M
Nakazawa
Miki
M
Ichikawa
Takanari
T
Shinozaki
Kazuo
K
Matsui
Minami
M
Nagamura
Yoshiaki
Y
Hirochika
Hirohiko
H
Ichikawa
Hiroaki
H
D001483:Base Sequence; D017931:DNA Primers; D018076:DNA, Complementary; D020869:Gene Expression Profiling / Q000379:methods*; D018745:Genome, Plant; D012275:Oryza / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012231:Rhizobium / Q000235:genetics
D017931:DNA Primers; D018076:DNA, Complementary