Variation in protein gene and intron content among land plant mitogenomes

• Published in: Mitochondrion Vol. 53; pp. 203 - 213
• Main Author: Mower, Jeffrey P.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.07.2020
• Subjects: Convergent evolution; Embryophyta - genetics; Evolution, Molecular; Gene content; Genome, Mitochondrial; Intron content; Introns; Land plants; Mitochondria - genetics; Mitochondrial genome (mitogenome); Nonvascular plants; Phylogeny; Trans-Splicing; Vascular plants; Land plants; Gene content; Intron content; Nonvascular plants; Mitochondrial genome (mitogenome); Convergent evolution; Vascular plants
• ISSN: 1567-7249; 1872-8278
• DOI: 10.1016/j.mito.2020.06.002

•Protein gene and intron content is compared among mitogenomes from 46 diverse land plants.•Protein gene content varies substantially among most land plant lineages, except liverworts and mosses.•Intron content is highly variable among the major land plant lineages, but relatively stable within each major lineage.•Ancestrally cis-spliced introns have shifted to trans-splicing dozens of times in lycophytes and seed plants.•Convergent evolution is a recurrent theme in mitogenomic evolution. The functional content of the mitochondrial genome (mitogenome) is highly diverse across eukaryotes. Among land plants, our understanding of the variation in mitochondrial gene and intron content is improving from concerted efforts to densely sample mitogenomes from diverse land plants. Here I review the current state of knowledge regarding the diversity in content of protein genes and introns in the mitogenomes of all major land plant lineages. Mitochondrial protein gene content is largely conserved among mosses and liverworts, but it varies substantially among and within other land plant lineages due to convergent losses of genes encoding ribosomal proteins and, to a lesser extent, genes for proteins involved in cytochrome c maturation and oxidative phosphorylation. Mitochondrial intron content is fairly stable within each major land plant lineage, but highly variable among lineages, resulting from occasional gains and many convergent losses over time. Trans-splicing has evolved dozens of times in various vascular plant lineages, particularly those with relatively higher rates of mitogenomic rearrangement. Across eukaryotes, mitochondrial protein gene and intron content has been shaped massive convergent evolution.