Huge mitochondrial genomes in embryophyta plants

Abstract

There are several embryophyta species with huge mitochondrial genomes, whose sizes exceed a million base pairs. We overview some common features of huge mitochondrial genomes: multiple chromosomes, increase in noncoding DNA, and loss of transfer RNA genes. These genomes arose in different evolutionary lines of Angiosperm plants via different processes: horizontal gene transfer from phylogenetically distant species to the ancient plant Amborella, DNA exchange between nucleus and mitochondrion in cucumber and melon (Cucumis, Cucurbitaceae), and recombination disturbance in Silene species (Caryophyllaceae).