EFFICIENT GENE TAGGING IN ARABIDOPSIS-THALIANA USING A GENE TRAP APPROACH

Large quantities of DNA sequence information about plant genes are rap idly accumulating in public databases, but to progress from DNA sequen ce to biological function a mutant allele for each of the genes ideall y should be available, Here we describe a gene trap construct that all owed us to disrupt transcribed genes with a high efficiency in Arabido psis thaliana. In the T-DNA vector used, the expression of a bacterial reporter gene coding for neomycin phosphotransferase II (nptII) depen ds on the in vivo generation of a translation fusion upon the T-DNA in tegration into the Arabidopsis genome, Analysis of 20 selected transge nic lines showed that 12 lines are T-DNA insertion mutants, The disrup ted genes analyzed encoded ribosomal proteins (three lines), aspartate tRNA synthase, DNA ligase, basic-domain leucine zipper DNA binding pr otein, ATP-binding cassette transporter, and five proteins of unknown function, Four tagged genes were new for Arabidopsis. The results pres ented here suggest that gene trapping, using nptII as a reporter gene, can be as high as 80% and opens novel perspectives for systematic gen e tagging in A. thaliana.