Research progress on physical mapping to chromosome and phylogenetic inference of 45S and 5S rDNA in fruit trees
Abstract：The research progress on physical mapping to chromosome and phylogenetic inference of 45S and 5S rDNA in fruit trees were reviewed in the paper, and their limitation and promising application prospect were also summarized at the end. Studies have shown that the loci of 45S and 5S rDNA on chro- mosome were independent from each other. By fluorescence in situ hybridization （FISH）, 45S rDNA re- peats, ranging from 1 to 4 pairs in fruit trees, were found to usually locate on distal satellites, short arm as well as centromere of chromosome. While the 5S repeats, ranging from 1 to 3 pairs, had no fixed loci on chromosomes. The number and location of rDNA loci have been used widely in identifying chromosomes, revising traditional karyotype and genome revolution in tree fruits. At the same time, internal transcribed spacer （ITS）, one of specific rDNA sequences, had been applied widely in phylogenetic restruction in fruit trees. However, duing to ITS polymorphism among individuals, it was necessary to detect putative pseu- dogenes. Additionally, utilization of multi-specific rDNA sequences to analyze phylogenetic implications probably has one bright future.
Keywords：Fruit treeRibosomal DNA （rDNA）Fluorescence in situ hybridization （FISH）Physical mappingPhylogenetic evolution
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)