First assembly of the gene-space of the Lolium multiflorum genome and comparison to other Poaceae genomes

The genome of a diploid, heterozygous L. multiflorum genotype was sequenced using the Illumina HiSeq2000 platform, resulting in approximately 69 Gb of raw data. These data were assembled into 130k scaffolds greater than 2kb in size and with a total assembly size of 574 Mb. We annotated 61k gene models with 81k splice variants to these scaffolds. Assessment of genome completeness using BUSCO analysis showed that 80.5% of BUSCOs were complete, indicating that the assembly provides a good representation of the gene content. A mining for simple sequence repeats (SSR) was performed between L. multiflorum and L. perenne and revealed 29,840 SSR loci for L. multiflorum and 46,780 for L. perenne, of which 4,601 were shared. The proteome of Lolium ssp. was compared with other Poaceae proteomes and the protein clusters including the SAUR-like auxin-responsive protein family, glutathione S-transferases, BTB-POZ and the photosystem II light harvesting complex gene B1B2 were found to be enriched. The number of protein clusters between L. multiflorum and L. perenne was compared and 86 were more abundant in L. multiflorum than in L. perenne and 293 reciprocally. High numbers of disease resistance genes and proteins involved in metal transport were found.