Rapid, large-scale generation of Ds transposant lines and analysis of the Ds insertion sites in rice.
Rapid, large-scale generation of a Ds transposant population was achieved using a regeneration procedure involving tissue culture of seed-derived calli carrying Ac and inactive Ds elements. In the F(2) progeny from genetic crosses between the same Ds and Ac starter lines, most of the crosses produced an independent germinal transposition frequency of 10-20%. Also, many Ds elements underwent immobilization even though Ac was expressed. By comparison, in a callus-derived regenerated population, over 70% of plants carried independent Ds insertions, indicating transposition early in callus formation. In the remaining population, the majority of plants carried only Ac. Most of the new Ds insertions were stably transmitted to a subsequent generation. An exceptionally high proportion of independent transposants in the regenerated population means that selection markers for transposed Ds and continual monitoring of Ac/Ds activities may not necessarily be required. By analyzing 1297 Ds-flanking DNA sequences, a genetic map of 1072 Ds insertion sites was developed. The map showed that Ds elements were transposed onto all of the rice chromosomes, with preference not only near donor sites (36%) but also on certain physically unlinked arms. Populations from both genetic crossing and tissue culture showed the same distribution patterns of Ds insertion sites. The information of these mapped Ds insertion sites was deposited in GenBank. Among them, 55% of Ds elements were on predicted open-reading frame (ORF) regions. Thus, we propose an optimal strategy for the rapid generation of a large population of Ds transposants in rice.
Kim
Chul Min
CM
Division of Applied Life Science, BK21 Program, Plant Molecular Biology & Biotechnology Research Center (PMBBRC), Gyeongsang National University, Jinju 660-701, Korea.
Piao
Hai Long
HL
Park
Soon Ju
SJ
Chon
Nam Soo
NS
Je
Byoung Il
BI
Sun
Bingyao
B
Park
Sung Han
SH
Park
Jin Young
JY
Lee
Eun Jin
EJ
Kim
Min Jung
MJ
Chung
Woo Sik
WS
Lee
Kon Ho
KH
Lee
Young Suk
YS
Lee
Jeung Joo
JJ
Won
Yong Jae
YJ
Yi
GiHwan
G
Nam
Min Hee
MH
Cha
Young Soon
YS
Yun
Doh Won
DW
Eun
Moo Young
MY
Han
Chang-deok
CD
D002874:Chromosome Mapping; D003433:Crosses, Genetic; D046508:Culture Techniques; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D018745:Genome, Plant; D008957:Models, Genetic; D016254:Mutagenesis, Insertional; D012275:Oryza / Q000235:genetics*; D011401:Promoter Regions, Genetic; D012038:Regeneration; D012639:Seeds / Q000235:genetics / Q000254:growth & development; D014170:Transformation, Genetic
D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D018744:DNA, Plant; C036483:T-DNA