Evolution of plant mitochondrial genomes via substoichiometric intermediates.
Comparison of the modern fertile maize mitochondrial genome (N) with an ancestral maize mitochondrial genome (RU) reveals a 12 kb duplication (containing the atpA gene) in the modern genome that is absent from the ancestor. Cloning, mapping, and sequencing of the relevant portions of the ancestral genome shows that this duplication probably arose via a three-stage recombination process involving substoichiometric intermediates. Comparison with analogous observations on yeast mitochondrial genomes suggests that this three-stage model of genome reorganization can be generally applied to plant mitochondrial genomes to explain both deletions and the creation of novel repeats, common features of plant mitochondrial genome evolution.
Small
I
I
Department of Botany, University of Edinburgh, Scotland.
Suffolk
R
R
Leaver
C J
CJ
D001483:Base Sequence; D005075:Biological Evolution; D003001:Cloning, Molecular; D004272:DNA, Mitochondrial / Q000235:genetics*; D008969:Molecular Sequence Data; D010944:Plants / Q000235:genetics*; D011995:Recombination, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D013269:Stochastic Processes
D004272:DNA, Mitochondrial