Oak Genome Decoded

The following is a translation of the press release issued by INRA on May 10, 2015. The abstract of the preliminary paper published in Molecular Ecology Resources in English is available: Decoding the oak genome: public release of sequence data, assembly, annotation and publication strategies, Christophe Plomion et al. Molecular Ecology Resources, 6 mai 2015 (DOI: 10.1111/1755-0998.12425).. Unfortunately, the paper itself is not in open access (contrary to what is stated in the press release). 

INRA and CEA research teams have just completed the genome sequencing of pedunculate oak (Quercus robur). This is the first sequencing of a species of the genus Quercus, which is widespread in the Northern Hemisphere. This research will, among other things, allow a better understanding of the coping mechanisms of trees in the face of environmental variations and provide elements to anticipate their responses to climate change. The present work is the subject of an article published in the open access journal Molecular Ecology Resources, prior to final publication of the results in the coming months.

Pedunculate oak (Aveyron, France), © INRA, A. Kremer

An iconic tree, the pedunculate oak (Quercus robur) is part of the largest botanical section of the genus Quercus: White Oak, of which there are 200 species present in Europe, Asia and America. Thanks to a consortium led by INRA Bordeaux-Aquitaine in partnership with the CEA's National Sequencing Centre (Génoscope), the pedunculate oak genome has been sequenced. Three years of work allowed the deciphering of the entire genetic information carried by its 12 pairs of chromosomes. The consortium has characterized 50,000 genes and estimated that half of the 1.5 billion base pairs of the genome consisted of repeated elements. This is the first such achievement for a species in the genus Quercus, which is important economically, ecologically, and also culturally in many countries.

The sequencing of the pedunculate oak genome is a unique approach for analyzing and understanding the function of the genes of this iconic tree. Its genome will thus be a reference for other White Oak species, but also for more distant species of the family Fagaceae (Chestnut or Beech). It will enable the study of the internal regulation of very long-lived species exposed to strong annual climate variations or even extreme events endured during their lifetime. This research will also facilitate the identification of genes involved in adaptation to the environment or in the symbiotic relationship between roots and mycorrhizal fungi (such as the truffle mycelium). They will also allow the identification of genes responsible for the biosynthesis of wood extracts, such as tannins and whiskey lactone, which give flavor and taste to wines and spirits. In terms of evolution, the genome sequence of the oak already allows researchers to analyze more closely the local adaptation and speciation processes, which explain the diversity of these trees that colonized very diverse habitats.

This work represents a major advance in the understanding of the biology, genetics, and evolution of trees, and will be invaluable in future research on the structure and function of the genome of these perennials. Beyond academic knowledge, this research opens up opportunities in more applied fields, in response to the many societal issues about the evolution of forests.

Translation: Charles Snyers