Epigenetic Regulation of Transgenerational Inheritance in Plants
Large proportions of eukaryotic genomes consist of transposable elements (TEs), predominantly retrotransposons. These are generally considered to be intra-chromosomal parasites. However, their periodical bursts of activity have influenced the organisation of host genomes and contributed to beneficial traits. Remarkably, a number of what turned out to be transposon-generated phenotypic innovations were selected by humans during plant domestication and breeding. Therefore, TEs can be considered as an attractive endogenous source of genetic variation. Unfortunately, there is at present no experimental/technological means to exploit this potential in a controlled fashion.
Our current research focuses on the epigenetic regulation of transcription and on molecular mechanisms contributing to formation of transgenerationally stable epigenetic states (epialleles). This includes environmental and developmental inputs that have direct consequences for the heritable alteration transcriptional states and contribution of retrotransposons to the genome-wide landscape of epigenetic regulation.
Recently, we revealed surprisingly selective epigenetic, environmental and developmental mechanisms controlling retrotransposition in Arabidopsis. Now we build on this knowledge and plan to establish a well-controlled retrotransposition system in a crop plant and liberate the innate genetic diversity buried in silenced TEs.
Reinders J., Wulff B. B. H., Mirouze M., Marí Ordóñez A., Dapp M., Rozhon W., Bucher E, Theiler G., Paszkowski J. (2009) Compromised stability of DNA methylation and transposon immobilization in mosaic Arabidopsis epigenomes. Genes & Dev. 23(8) : 939-50
Ito H, Gaubert H, Bucher E, Mirouze M, Vaillant I, Paszkowski J. (2011) An siRNA pathway prevents transgenerational retrotransposition in plants subjected to stress. Nature 472(7341) : 115-19.
Mirouze M, Lieberman-Lazarovich M, Aversano R, Bucher E, Nicolet J, Reinders J, Paszkowski J. (2012) Loss of DNA methylation affects the recombination landscape in Arabidopsis. Proc Natl Acad Sci U S A. 109(15) : 5880-5
Reinders J, Mirouze M, Nicolet J, Paszkowski J.(2013) Parent-of-origin control of transgenerational retrotransposon proliferation in Arabidopsis. EMBO Rep. 2013 Aug 30; 14(9) : 823-8
Please note that the contents of this page have been extracted from the Sainsbury Lab website. Fuller version here : http://www.slcu.cam.ac.uk/research/paszkowski-group