Gene duplication and concerted evolution of mitochondrial DNA in crane species.
The gene duplication in mitochondrial DNA (mtDNA) has been reported in diverse bird taxa so far. Although many phylogenetic and population genetic analyses of cranes were carried out based on mtDNA diversity, whether mtDNA contains duplicated regions is unknown. To address the presence or absence of gene duplication in cranes and investigate the molecular evolutionary features of crane mtDNA, we analyzed the gene organization and the molecular phylogeny of mtDNA from 13 crane species. We found that the mtDNA in 13 crane species shared a tandem duplicated region, which consists of duplicated sequence sets including cytochrome b (Cytb), NADH6, control region (CR) and three genes of tRNA. The gene order in the duplicated region was identical among all the 13 crane species, and the nucleotide sequences found within each individual showed high similarities. In addition, phylogenetic trees based on homologous sequences of CR and Cytb indicated the possibility of concerted evolution among the duplicated genes. The results suggested that the duplication event occurred in the common ancestor of crane species or some older ancestors.
Department of Natural History Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan.
Takuya
T
Akiyama
Department of Natural History Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan; Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan.
Chizuko
C
Nishida
Red-crowned Crane Conservancy, Kushiro 085-0036, Japan.
Kunikazu
K
Momose
Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba 305-8506, Japan.
Manabu
M
Onuma
Osaka Municipal Tennoji Zoological Gardens, Osaka 543-0063, Japan.
Kazutoshi
K
Takami
Department of Natural History Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan; Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan. Electronic address: masudary@mail.sci.hokudai.ac.jp.
Ryuichi
R
Masuda
D000818:Animals; D001717:Birds / Q000145:classification / Q000235:genetics*; D045303:Cytochromes b / Q000145:classification / Q000235:genetics; D004247:DNA / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D004272:DNA, Mitochondrial / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D019143:Evolution, Molecular; D020440:Gene Duplication; D010802:Phylogeny; D012343:RNA, Transfer / Q000145:classification / Q000235:genetics; D017422:Sequence Analysis, DNA
D004272:DNA, Mitochondrial; D004247:DNA; D012343:RNA, Transfer; D045303:Cytochromes b
Concerted evolution; Crane; Duplication; Gruidae; Mitochondrial genome; Molecular evolution