Multiple origins and nrDNA internal transcribed spacer homeologue evolution in the Glycine tomentella (Leguminosae) allopolyploid complex.

摘要: Despite the importance of polyploidy in evolution plants, patterns molecular and genomic interactions following are not well understood. Nuclear ribosomal DNA is particularly complex with respect to these interactions. The composition nrDNA tandem arrays influenced by intra- interlocus concerted their expression characterized such as nucleolar dominance. To understand it important study them diverse natural polyploid systems. In this we use direct sequencing isolate characterize internal transcribed spacer (ITS) homeologues from multiple accessions six different races Glycine tomentella allopolyploid complex. results indicate that most both homeologous repeats present, but there significant biases copy number toward one homeologue, possibly resulting evolution. predominant homeologue often differs between within a race. A phylogenetic analysis ITS sequences provides evidence for origins several races. This will provide useful system future studies variation expression.