Plant mitochondrial genome diversity: The genomics revolution

Abstract

Mitochondrial genomes are remarkably diverse among green plants, and the explosion of genome sequencing over the last 30 years has greatly expanded our understanding of this diversity. Genome sizes range from 20 kilobases in some green algae to several megabases in certain angiosperms. The repertoire of genes, introns, repeats, and RNA editing is also variable, as is the amount of DNA integrated from foreign sources, including the plastid, nucleus, and other species. Genome structure is labile due to recombination involving large and small repeats, which produces multiple genomic arrangements within species and loss of synteny among species. In this review, we describe the range of diversity among plant mitochondrial genomes, discuss how the genomics revolution has advanced our understanding of this diversity, and stress the importance of future studies to resolve remaining uncertainties.