title: The mitochondrial genome of the Basidiomycete fungus Pleurotus ostreatus (oyster mushroom).
abstract: In this study, the full mitochondrial genome of a basidiomycete fungus, Pleurotus ostreatus, was sequenced and analyzed. It is a circular DNA molecule of 73 242 bp and contains 44 known genes encoding 18 proteins and 26 RNA genes. The protein-coding genes include 14 common mitochondrial genes, one ribosomal small subunit protein 3 gene, one RNA polymerase gene and two DNA polymerase genes. In addition, one RNA and one DNA polymerase genes were identified in a mitochondrial plasmid. These two genes show relatively low similarities to their homologs in the mitochondrial genome but they are nearly identical to the known mitochondrial plasmid genes from another Pleurotus ostreatus strain. This suggests that the plasmid may mediate the horizontal gene transfer of the DNA and RNA polymerase genes into mitochondrial genome, and such a transfer may be an ancient event. Phylogenetic analysis based on the cox1 ORFs verified the traditional classification of Pleurotus ostreatus among fungi. However, the discordances were observed in the phylogenetic trees based on the six cox1 intronic ORFs of Pleurotus ostreatus and their homologs in other species, suggesting that these intronic ORFs are foreign DNA sequences obtained through HGT. In summary, this analysis provides valuable information towards the understanding of the evolution of fungal mtDNA.
authors.affiliation: School of Biological Sciences, University of Hong Kong, Pokfulam, Hong Kong, HKSAR, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Fanya
authors.initials: F
authors.lastname: Zeng
authors.forename: Chung Chau
authors.initials: CC
authors.lastname: Hon
authors.forename: Yizheng
authors.initials: Y
authors.lastname: Zhang
authors.forename: Frederick Chi Ching
authors.initials: FC
authors.lastname: Leung
mesh_terms: D000595:Amino Acid Sequence; D001487:Basidiomycota / Q000145:classification / Q000235:genetics*; D004271:DNA, Fungal / Q000235:genetics; D021901:DNA, Intergenic / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry / Q000235:genetics; D022761:Gene Transfer, Horizontal; D054629:Genome, Mitochondrial; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D020161:Physical Chromosome Mapping; D020076:Pleurotus / Q000235:genetics*; D012194:RNA-Directed DNA Polymerase / Q000737:chemistry / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D004271:DNA, Fungal; D021901:DNA, Intergenic; D004272:DNA, Mitochondrial; D012194:RNA-Directed DNA Polymerase; D012321:DNA-Directed RNA Polymerases