Transposable Elements

Part of the Compendium of Plant Genomes book series (CPG)


Transposable elements (TEs) including retrotransposons and DNA transposons are the major DNA components in soybean (Glycine max L. Merr.), accounting for approximately 60% of the soybean reference genome. The majority of soybean TEs are long terminal repeat retrotransposons that were amplified in the past a few million years (myr). Overall, the TEs were preferentially accumulated in the pericentromeric regions of all chromosomes, but different classes/superfamilies/families of TEs generally exhibited different patterns of distribution along chromosomes. Such a distribution pattern appears to be the outcome of TE insertion bias as well as natural selection purging deleterious genic TE insertions. Despite their periodic proliferation, many TEs have accumulated various deletions through unequal homologous recombination and illegitimate recombination to become “dead” copies and to counteract genome expansion caused by periodic TE amplification. The majority of intact TEs appear to be inactivated, either transcriptionally or transpositionally, by epigenetic mechanisms such as DNA methylation, histone modification, and small RNA-mediated silencing. Nevertheless, active endogenous TEs have been found and are being used to develop TE-based soybean mutants for discovery of genes underlying traits of agronomic importance.


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© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Department of AgronomyPurdue UniversityWest LafayetteUSA

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