ANALYSIS OF THE CHROMOSOMAL DISTRIBUTION OF TRANSPOSON-CARRYING T-DNAS IN TOMATO USING THE INVERSE POLYMERASE CHAIN-REACTION

We are developing a system for isolating tomato genes by transposon mu tagenesis. In maize and tobacco, the transposon Activator (Ac) transpo ses preferentially to genetically linked sites. To identify transposon s linked to various target genes, we have determined the RFLP map loca tions of Ac- and Dissociation (Ds)-carrying T-DNAs in a number of tran sformants. T-DNA flanking sequences were isolated using the inverse po lymerase chain reaction (IPCR) and located on the RFLP map of tomato. The authenticity of IPCR reaction products was tested by several crite ria including nested primer amplification, DNA sequence analysis and P CR amplification of the corresponding insertion target sequences. We r eport the RFLP map locations of 37 transposon-carrying T-DNAs. We also report the map locations of nine transposed Ds elements. T-DNAs were identified on all chromosomes except chromosome 6. Our data revealed n o apparent chromosomal preference for T-DNA integration events. Lines carrying transposons at known map locations have been established whic h should prove a useful resource for isolating tomato genes by transpo son mutagenesis.