<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Conifer genomes are large and stably diploid, in contrast to angiosperms, which are more variable both in genome size and ploidy. Conifer genomes are characterised by multiple gene families and pseudogenes, contain large inter-gene regions and a considerable proportion of repetitive sequences. All members of plant retrotransposon orders have been identified in gymnosperm genomes, however active elements have not been described. Investigation of transposable elements in Scots pine (Pinus sylvestris L.) could offer insights into transposon-mediated reorganisation under stress conditions in complex and ancient plant genomes. Nine Pinus sylvestris specific markers were developed to hypothetical long terminal repeats (LTRs) from differentially expressed retrotransposon-like fragments after heat stress and insect damage. Genetic diversity of 150 trees from a naturally regenerated pine stand was investigated using the IRAP method. The developed markers revealed high levels of genetic diversity and were able to distinguish subpopulations growing in long-term differential environmental conditions. Somaclonal variation was also investigated using these markers and polymorphic fragments were identified between ramets of Scots pine clones growing in two different plantations, possibly indicating evidence of recent transposition events. Sequencing of the polymorphic fragments identified two groups of sequences containing LTR sequences of an unknown retrotransposon with homology to the LTRs of the Copia-17-PAb-I element.</p></abstract>

Conifer genomes are large and stably diploid, in contrast to angiosperms, which are more variable both in genome size and ploidy. Conifer genomes are characterised by multiple gene families and pseudogenes, contain large inter-gene regions and a considerable proportion of repetitive sequences. All members of plant retrotransposon orders have been identified in gymnosperm genomes, however active elements have not been described. Investigation of transposable elements in Scots pine (Pinus sylvestris L.) could offer insights into transposon-mediated reorganisation under stress conditions in complex and ancient plant genomes. Nine Pinus sylvestris specific markers were developed to hypothetical long terminal repeats (LTRs) from differentially expressed retrotransposon-like fragments after heat stress and insect damage. Genetic diversity of 150 trees from a naturally regenerated pine stand was investigated using the IRAP method. The developed markers revealed high levels of genetic diversity and were able to distinguish subpopulations growing in long-term differential environmental conditions. Somaclonal variation was also investigated using these markers and polymorphic fragments were identified between ramets of Scots pine clones growing in two different plantations, possibly indicating evidence of recent transposition events. Sequencing of the polymorphic fragments identified two groups of sequences containing LTR sequences of an unknown retrotransposon with homology to the LTRs of the Copia-17-PAb-I element.

Development and Characterisation of Irap Markers From Expressed Retrotransposon-like sequences in <italic>Pinus sylvestris</italic> L.

Genetic Resource Centre, Latvian State Forest Research Institute „Silava”, Rīgas iela 111, LV-2169, Salaspils, LATVIA

Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Development and Characterisation of Irap Markers From Expressed Retrotransposon-like sequences in  L.

IRAP MARĶIERU IZVEIDOŠANA NO EKSPRESĒTĀM RETROTRANSPOZONIEM LĪDZĪGĀM SEKVENCĒM UN TO RAKSTUROŠANA

Conifer genomes are large and stably diploid, in contrast to angiosperms, which are more variable both in genome size and ploidy. Conifer genomes are...

Development and Characterisation of Irap Markers From Expressed Retrotransposon-like sequences in Pinus sylvestris L.

Published Online: Jul 17, 2014

Page range: 485 - 492

Received: Sep 17, 2013

DOI: https://doi.org/10.2478/prolas-2013-0082

Keywords
IRAP, transposable elements, retrotransposons, Scots pine

© 2013 Angelika Voronova and Dainis Ruņģis

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Development and Characterisation of Irap Markers From Expressed Retrotransposon-like sequences in Pinus sylvestris L.

Published Online: Jul 17, 2014

Page range: 485 - 492

Received: Sep 17, 2013

DOI: https://doi.org/10.2478/prolas-2013-0082

KeywordsIRAP, transposable elements, retrotransposons, Scots pine

© 2013 Angelika Voronova and Dainis Ruņģis

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
IRAP, transposable elements, retrotransposons, Scots pine