Nuclear ribosomal ITS sequences and phylogeny in East AsianAconitum subgenusAconitum (Ranunculaceae), with special reference to extensive polymorphism in individual plants |
| |
Authors: | Y Kita M Ito |
| |
Institution: | (1) Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, 113-0033 Tokyo, Japan;(2) Department of Systems Sciences, University of Tokyo, 153-8902 Komaba, Tokyo, Japan |
| |
Abstract: | Internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA (nrDNA) were used to examine the phylogeny of East Asian aconites. Individual aconites were discovered to contain as many as eight different ITS sequences after cloning and PCR-SSCP (single-stranded conformational polymorphisms) analysis. We identified eight putative ITS pseudogenes from four taxa with low predicted secondary structure stability and high substitution rates. Maximum likelihood (ML) and neighbor-joining (NJ) methods were used for phylogenetic reconstruction. The ITS trees agree with the previous chloroplast DNA (cpDNA) tree for the vast majority of the taxa. We found two East Asian clades in the ITS trees: 1) a clade with the Chinese diploid,Aconitum volubile and East Asian tetraploids, and 2) a clade of East Asian diploids and Siberian tetraploids. In the former clade, most tetraploid taxa appear to be polyphyletic; sequences from individual plants did not correspond to recognized taxonomic units. This indicates a recent divergence of the East Asian tetraploids. |
| |
Keywords: | Ranunculaceae Aconitum ITS polymorphism pseudogenes phylogeny |
本文献已被 SpringerLink 等数据库收录! |
|