Novel rearrangements in the mitochondrial genomes of the Ceramiales (Rhodophyta) and evolutionary implications
Author:
Seo Min Ho,Kang Shin Chan,Kim Kyeong Mi,Kwak Min Seok,Jo Jihoon,Choi Han-Gu,Boo Ga Hun,Yoon Hwan Su
Abstract
The Ceramiales is the most diverse and species-rich group (2,669 spp.) of red algae, and it is widely distributed from tropical to polar oceans. Mitochondrial genomes (mitogenomes) and other genes have contributed to our knowledge regarding the classification and phylogeny of this diverse red algal group; however, the mitogenome architecture remains understudied. Here, we compared 42 mitogenomes, including 19 newly generated in this study, to expand our knowledge. The number of genes in mitogenome varied from 43 to 68 due to gene duplication. The mitogenome architecture was also variable, categorized into four types (A–D): type A = ancestral type with a basic composition; type B = those with inverse transpositions; type C = those with inverted duplications; and type D = those with both inversion and duplication. The palindromic and inverted repeats were consistently found in flanking regions of the rearrangement, especially near the cob and nad6 genes. The three rearranged mitogenome architectures (types B, C, D) are the first report of these in red algae. Phylogenetic analyses of 23 protein-coding genes supported the current familial classification of the Ceramiales, implying that the diversity of mitogenome architecture preceded the phylogenetic relationships. Our study suggests that palindromic and inverted repeats may drive mitogenome architectural variation.
Funder
National Research Foundation of Korea
Cooperative Research Program for Agriculture Science and Technology Development
Rural Development Administration
National Marine Biodiversity Institute of Korea
Publisher
The Korean Society of Phycology
Subject
Plant Science,Aquatic Science,Ecology, Evolution, Behavior and Systematics