The evolution of intergenic spacers of the 5S rDNA genes in the Drosophila obscura group: Are these sequences suitable for phylogenetic analyses?

作者：Grau R; Bachmann L

来源：Biochemical Systematics and Ecology, 1997, 25(2): 131-139.

DOI：10.1016/S0305-1978(96)00073-7

• 5S rDNA spacers
• Drosophila obscura group
• genome evolution
• molecular evolution
• phylogenetic analysis
• repetitive DNA
• tandemly repeated DNA

The 5S rDNA repeats of ten species of the Drosophila obscura group were amplified by PCR and characterized. In the coding regions of the 5S rDNA genes, only very few differences were detected between the species. The non-coding intergenic spacers of the sibling species D. subobscura, D. madeirensis and D. guanche, and D. bifaciata and D. imaii, respectively, are almost identical, but differ substantially between other more distantly related species. For the most part, short insertions/deletions are the main source of interspecific sequence variability. Consequently, an alignment of the intergenic 5S rDNA spacers of distantly related species is almost impossible. The value of phylogenetic networks based on the 5S rDNA spacer sequences appears to be rather limited compared to those derived from other data with too few informative differences between closely related species and too many between those slightly more distantly related.

• 出版日期1997-3