| Cytoplasmic male sterility (CMS) phenotype in common bean has been associated with the insertion in the mitochondrial genome of a foreign DNA sequence coined pvs. Antibodies raised against the largest open reading frame, pvs-orf239, demonstrated that expression of ORF239 is tissue-specific and found only in the reproductive tissues of the male sterile plant(CMS-Sprite). Definitive evidence that ORF239 is the causal agent in CMS was provided by transgenic tobacco plants expressing ORF239 resulting in male sterile plant phenotypes with similar ORF239 localization. Finally, post-translational regulation of ORF239 by a matrix mitochondrial serine protease with enzymatic characteristics similar of Lon protease was demonstrated. |
