Complete sequence of the mitochondrial DNA of the chlorophyte alga Prototheca wickerhamii. Gene content and genome organization.

摘要: Abstract The complete nucleotide sequence of the circular mitochondrial (mt) DNA chlorophyte alga Prototheca wickerhamii has been determined (55,328 base-pairs, A+T content 74·2%). genes identified encode three subunits cytochome oxidase, apocytochrome b, nine NADH dehydrogenase complex (nad1 to 7, nad4L and nad9), ATPase (atp6, atp9, atp1 (also referred as atpA )), ribosomal RNAs (5 S (rrn5), small subunit (srn) large (lrn) RNA), 26 tRNAs, 13 ribosome proteins. A total five group I introns reside in lrn cox1, two which include intronic open reading frames (ORFs). Five free-standing ORFs longer than 60 codons are present. Three these counterparts encoding proteins unknown function plant mitochondria (orf25 orfB angiosperms orf244 liverwort), whereas them unique. Mitochondrial encoded on both strands a way that suggest existence transcription units, each including approximately one half genome. intergenic regions is believed initiate terminate about ten times other (1118 1993 nt versus 100 150 nt). 29 recurring motifs (30 200 long) have found regions. Nine different types present, most arranged tandem repeats. These may be implicated transcription, e.g. signals for initiation and/or processing. Phylogenetic analysis basis cox1 gene strongly suggested P. genomes monophyletic. finding plant-specific such orf25, orf244, rrn5 corroborates this idea.