Abstract
We have developed a rice gene targeting (GT) system by homologous recombination. As a model for an endogenous natural gene to be targeted, we have chosen the Waxy gene and achieved a reproducible GT without any detectable ectopic events. All the targeted plants were heterozygotes at the Waxy locus and the modified waxy allele segregated into their selfed progeny in Mendelian fashion (Annual Meeting of JSPP, 2002; 2003). Since our GT procedure with a strong positive-negative selection is in principle applicable to any rice gene, we have begun to apply one of multiple genes residing adjacent to multi-copy retroelements. We chose the Adh1 and Adh2 genes flanking a copia-like and a gypsy-like retrotransposon on chromosome 11. We outline our experimental design including the constructed vectors and describe PCR analysis of rice calli obtained for GT of these Adh genes.
