Boechera retrofracta Assembly. Boechera retrofracta

Closely related to the model plant Arabidopsis thaliana, the genus Boechera is known to contain both sexual and apomictic species or accessions within the species. Boechera retrofracta is a diploid sexually reproducing species and is thought to be an ancestral parent species of the apomictic species Boechera divaricarpa.Findings. Here we report the de novo assembly of the B. retrofracta genome using short Illumina and Roche reads from 1 paired-end and 3 mate pair libraries. The distribution of 23-mers from the paired end library has indicated a low level of heterozygosity and the presence of detectable duplications and triplications. The genome size was estimated to be equal 227 Mb.N50 of the assembled scaffolds was 2.3 Mb. 27048 protein-coding genes were predicted using a hybrid approach that combines homology-based and de novo methods. Also repeats, tRNA and rRNA genes were annotated. Finally, genes of B. retrofracta and 6 other Brassicaceae species were used for phylogenetic tree reconstruction.Conclusions. B. retrofracta is a plant of particular interest as an ancestor of various hybrids including apomictic species. An assembled genome of B. retrofracta will help in the challenging assembly of the highly heterozygous genomes of hybrid apomictic species such as B. divaricarpa, and to decipher the hybridogenesis events that took place in the formation of apomictic Boechera accessions.