The protein-encoding gene T-urf13 is not edited in maize mitochondria.
RNA editing of T-urf13, a gene specific to the mitochondria of cytoplasmic male-sterile, type-T (cms-T) maize, and an adjacent, cotranscribed gene orf221, have been studied by cDNA sequencing. No editing was detected in 22 cDNA clones. This is the only report of a polypeptide-encoding gene in higher-plant mitochondria that is not edited. T-urf13 may not be edited because it is derived largely from the coding and flanking regions, which are rarely edited, of a ribosomal RNA gene. orf221 is edited; however, the similarity between the predicted amino acid sequences of orf221 in cms-T and normal cytoplasms is not increased.