Cytochrome oxidase subunit II gene is adjacent to an initiator methionine tRNA gene in soybean mitochondrial DNA.

The nucleotide sequence of the cytochrome oxidase subunit II (COII) gene from soybean mitochondria reveals a high degree of sequence conservation to other plant COII sequences. The greatest homology is to pea (97.9%) and the homology extends for some distance both 5' and 3' from the gene. Upstream from the breakpoint in homology with the pea sequence there is a tRNA gene identified as the initiator methionine by homology to known plant tRNA genes. The COII coding sequence appears to be present at a single location in the soybean mitochondrial genome, however some portion of the 5' flanking region is repeated at other sites in the genome. The transcription from the cloned region is complex and is complicated by the presence of the repeated sequence.