Two novel gene orders and the role of light-strand replication in rearrangement of the vertebrate mitochondrial genome

• Published in: Molecular biology and evolution Vol. 14; no. 1; pp. 91 - 104
• Main Authors: Macey, J R, Larson, A, Ananjeva, N B, Fang, Z, Papenfuss, T J
• Format: Journal Article
• Language: English
• Published: United States 01-01-1997
• Subjects: Amino Acid Sequence; Animals; Base Sequence; DNA Primers - genetics; DNA Replication - genetics; DNA, Mitochondrial - genetics; Evolution, Molecular; Freshwater; Gene Rearrangement; Genome; Lizards - genetics; Molecular Sequence Data; Multigene Family; Nucleic Acid Conformation; Phylogeny; Rana limnocharis; Ranidae - genetics; Reptiles - genetics; RNA, Transfer, Asn - chemistry; RNA, Transfer, Asn - genetics; RNA, Transfer, Cys - chemistry; RNA, Transfer, Cys - genetics; Uromastix acanthinurus; Vertebrates - genetics
• ISSN: 0737-4038; 1537-1719
• DOI: 10.1093/oxfordjournals.molbev.a025706

Two novel mitochondrial gene arrangements are identified in an agamid lizard and a ranid frog. Statistical tests incorporating phylogeny indicate a link between novel vertebrate mitochondrial gene orders and movement of the origin of light-strand replication. A mechanism involving errors in light-strand replication and tandem duplication of genes is proposed for rearrangement of vertebrate mitochondrial genes. A second mechanism involving small direct repeats also is identified. These mechanisms implicate gene order as a reliable phylogenetic character. Shifts in gene order define major lineages without evidence of parallelism or reversal. The loss of the origin of light-strand replication from its typical vertebrate position evolves in parallel and, therefore, is a less reliable phylogenetic character. Gene junctions also evolve in parallel. Sequencing across multigenic regions, in particular transfer RNA genes, should be a major focus of future systematic studies to locate novel gene orders and to provide a better understanding of the evolution of the vertebrate mitochondrial genome.