Red algal phylogeny and evolution based on mitochondrial genome.

Abstract

The Florideophyceae (5 subclasses and 31 orders) and Bangiophyceae (1 subclass and 1 order) distribute in both marine and freshwater habitats, and cover the most described red algal diversity, ca. 7,100 species (98% of Rhodophyta). The monophyly those two classes and relationships among subclasses were well-supported in many phylogenetic analyses, however, interordinal phylogeny remain largely unknown in the subclass Rhodymeniophycidae. In order to resolve ordinal relationships and evolution of the subclass, we have determined 11 mitochondrial genomes (mtDNA) from representative species and compared with published data. Concatenated phylogeny based on 37 mtDNA (6,345 aminoi acid data) of red algae showed stronger support among order level than previous studies. The mtDNA synteny comparison showed 47 events of gene evolution (indel and rearrangement) among Bangiophyceae, Hidenbrandiophycidae, Nemaliophycidae, Corallinophycidae, Ahnfeltiophycidae, and Rhodymeniophycidae. We demonstrate that all rhodymeniophycidan mtDNA have conserved architectures with little variation of contents. Based on the best phylogeny, we inferred the ancestral mtDNA content, evolution and reduction of protein coding genes in red algae.phyly those two classes and relationships among subclasses were well-supported in many phylogenetic analyses, however, interordinal phylogeny remain largely unknown in the subclass Rhodymeniophycidae. In order to resolve ordinal relationships and evolution of the subclass, we have determined 11 mitochondrial genomes (mtDNA) from representative species and compared with published data. Concatenated phylogeny based on 37 mtDNA (6,345 aminoi acid data) of red algae showed stronger support among order level than previous studies. The mtDNA synteny comparison showed 47 events of gene evolution (indel and rearrangement) among Bangiophyceae, Hidenbrandiophycidae, Nemaliophycidae, Corallinophycidae, Ahnfeltiophycidae, and Rhodymeniophycidae. We demonstrate that all rhodymeniophycidan mtDNA have conserved architectures with little variation of contents. Based on the best phylogeny, we inferred the ancestral mtDNA content, evolution and reduction of protein coding genes in red algae.