title: Generation of a flanking sequence-tag database for activation-tagging lines in japonica rice.
abstract: We have generated 47,932 T-DNA tag lines in japonica rice using activation-tagging vectors that contain tetramerized 35S enhancer sequences. To facilitate use of those lines, we isolated the genomic sequences flanking the inserted T-DNA via inverse polymerase chain reaction. For most of the lines, we performed four sets of amplifications using two different restriction enzymes toward both directions. In analyzing 41,234 lines, we obtained 27,621 flanking sequence tags (FSTs), among which 12,505 were integrated into genic regions and 15,116 into intergenic regions. Mapping of the FSTs on chromosomes revealed that T-DNA integration frequency was generally proportional to chromosome size. However, T-DNA insertions were non-uniformly distributed on each chromosome: higher at the distal ends and lower in regions close to the centromeres. In addition, several regions showed extreme peaks and valleys of insertion frequency, suggesting hot and cold spots for T-DNA integration. The density of insertion events was somewhat correlated with expressed, rather than predicted, gene density along each chromosome. Analyses of expression patterns near the inserted enhancer showed that at least half the test lines displayed greater expression of the tagged genes. Whereas in most of the increased lines expression patterns after activation were similar to those in the wild type, thereby maintaining the endogenous patterns, the remaining lines showed changes in expression in the activation tagged lines. In this case, ectopic expression was most frequently observed in mature leaves. Currently, the database can be searched with the gene locus number or location on the chromosome at http://www.postech.ac.kr/life/pfg/risd. On request, seeds of the T(1) or T(2) plants will be provided to the scientific community.
authors.affiliation: Department of Life Science and National Research Laboratory of Plant Functional Genomics, Pohang University of Science and Technology, POSTECH, Republic of Korea.
authors.forename: Dong-Hoon
authors.initials: DH
authors.lastname: Jeong
authors.forename: Suyoung
authors.initials: S
authors.lastname: An
authors.forename: Sunhee
authors.initials: S
authors.lastname: Park
authors.forename: Hong-Gyu
authors.initials: HG
authors.lastname: Kang
authors.forename: Gi-Gyeong
authors.initials: GG
authors.lastname: Park
authors.forename: Sung-Ryul
authors.initials: SR
authors.lastname: Kim
authors.forename: Jayeon
authors.initials: J
authors.lastname: Sim
authors.forename: Young-Ock
authors.initials: YO
authors.lastname: Kim
authors.forename: Min-Kyung
authors.initials: MK
authors.lastname: Kim
authors.forename: Seong-Ryong
authors.initials: SR
authors.lastname: Kim
authors.forename: Joowon
authors.initials: J
authors.lastname: Kim
authors.forename: Moonsoo
authors.initials: M
authors.lastname: Shin
authors.forename: Mooyoung
authors.initials: M
authors.lastname: Jung
authors.forename: Gynheung
authors.initials: G
authors.lastname: An
mesh_terms: D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D004269:DNA, Bacterial / Q000235:genetics; D030541:Databases, Genetic; D020869:Gene Expression Profiling; D009154:Mutation; D012275:Oryza / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial; C036483:T-DNA