A gapless genome sequence of the fungus Botrytis cinerea

Following earlier incomplete and fragmented versions of agenome sequence for the grey mouldBotrytis cinerea, a gapless,near-finished genome sequence forB. cinereastrain B05.10 isreported. The assembly comprised 18 chromosomes and wasconfirmed by an optical map and a genetic map based onapproximately 75 000 single nucleotide polymorphism (SNP)markers. All chromosomes contained fully assembled centromericregions, and 10 chromosomes had telomeres on both ends. Thegenetic map consisted of 4153 cM and a comparison of thegenetic distances with the physical distances identified 40 recom-bination hotspots. The linkage map also identified two muta-tions, located in the previously described genesBos1 andBcsdhB, that conferred resistance to the fungicides boscalid andiprodione. The genome was predicted to encode 11 701 proteins.RNAseq data from>20 different samples were used to validateand improve gene models. Manual curation of chromosome 1revealed interesting features, such as the occurrence of a dicis-tronic transcript and fully overlapping genes in opposite orienta-tions, as well as many spliced antisense transcripts. Manualcuration also revealed that the untranslated regions (UTRs) ofgenes can be complex and long, with many UTRs exceedinglengths of 1 kb and possessing multiple introns. Community annotation is in progress.