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RNA editing is a post transcriptional RNA modification process that alters genetic information on mRNA of both mitochondria and chloroplast. Commonly, specific cytosine residues in mRNA molecules are substituted with uracil residues to provide coding sequences for functional proteins. However, the mechanism of this RNA editing process is still unclear. ATP-synthase genes encode ATP complexes, which are important enzymes synthesizing ATP in mitochondria. In this study, we investigated RNA editing sites in the members of ATP-synthase genes in the mitochondria of Borassus flabellifer. RNA editing sites of atp1 atp6 and atp9 transcripts were analyzed by using both RNA editing prediction program and gene cloning and sequencing of using mtDNA and cDNA. The analysis showed 11, 25 and 10 RNA editing sites in atp1 atp6 and atp9 transcripts, respectively. All of the editing sites were C bases substituted with U bases. These mostly occurred at the second base of each codon, and occasionally at the first base position. Consequently, these U substitutions caused amino acid changes from original transcripts in all edited mRNA. These results support the essential of RNA editing process for controlling the production of functional ATP-synthase in the mitochondrial inner membrane.
Keywords: ATP-synthase gene; Borassus flabellifer; RNA editing
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