Type II DNATopoisomerase (Top2) as Promising Molecular Marker for Phylogenetic Analysis in Rhodophyta.

Taxonomic uncertainty still exists in the Rhodophyta, and more suitable molecular markers for their phylogeny are required to establish conclusively their taxonomic relationship. In this paper, we describe sequencing, characterisation of partial nucleotide sequence of the TOP2 and phylogenetic analysis of the Top2, which is translated fromthe TOP2 in Porphyra yezoensis. The length of the partial nucleotide sequence of TOP2 was 1,208 bp and the predicted amino acid sequence was 402 amino acids. The present sequences matched to known TOP2 or Top2 sequences in the public databases and consensus sequences for the motifs [Top2 signature, ATP/GTP- binding site motif A (P-loop), etc.] are indicated in the amino acid sequences. In our phylogenetic trees, the Rhodophyta occupied an independent position within the crown eukaryotes. Thus, we can advocate that we succeeded in the determination of TOP2 andTop2 sequencesofP. yezoensis and Top2 may be a promising marker for phylogenetic analysis of the Rhodophyta. This is the first report to deal with Top2 from the Rhodophyta. [ABSTRACT FROM AUTHOR]