Differential display of immature anther cDNA was carried out between restorer and maintainer lines of [ms-bo] cytoplasmic male sterile rice. One clone (DD2-3) was identified to be specific to restorer line. However DD2-3 was mapped on the chromosome 11 and was not linked to fertility-restorer gene, Rf-1. Full length cDNA of DD2-3 was obtained and the predicted amino acid sequence contains leucine zipper structure, followed by nucleotide binding site (NBS) and leucine rich repeats (LRR). These structures are characteristics of the NBS-LRR class of plant disease-resistant genes. The transcripts of DD2-3 were detected in the anthers at the microspore stage and leaves.