(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Eukaryota: NE > Viridiplantae: NE > Streptophyta: NE > Streptophytina: NE > Embryophyta: NE > Tracheophyta: NE > Euphyllophyta: NE > Spermatophyta: NE > Magnoliophyta: NE > Mesangiospermae: NE > eudicotyledons: NE > Gunneridae: NE > Pentapetalae: NE > rosids: NE > malvids: NE > Brassicales: NE > Brassicaceae: NE > Brassiceae: NE > Brassica: NE > Brassica napus: NE
Warning: This entry is a compilation of different species or line or strain with more than 90% amino acid identity. You can retrieve all strain data
(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) Brassica napus var. napus: N, E.
Brassica oleracea var. oleracea: N, E.
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA MALEALAGITNDQITRSWKASTRAYNTDHFHKEEERETVVVAFAPSFLEK DWIAPENKSPFGETKMKRAQFPCMRSIGNDVDATVNESFLKNFQVLTSPT TSFCDYVKTVVDSRQSQRIVFTGHSTGGATAILATVWYLETYFKKPRGGF PLPEPLCMTFGAPLVGDYVFKHALGRENWSRFFVNFVTRFDIVPRIMLAR KASTKQALPRVLSQLDPRVAIQENDQSIPVFYTTVMKETATVAHQAVCEL IGYGDAFLETFSSFLDLSPYRPAGIFVFSTGTGLVSVSNSDAILQILFYA SQSSNQHELSLVPFQSIKDHRSYEEMVHSMAMKPLNHLDLHHLPLDGDPM LRDLGLSTRARQCVCAAFEAEKQRVDNQTKIYNKLPKIVEKLTWIEDEYK PRCKTHKVGYYDSFKYSNEEKDFKANVSRAELAGLFDEVLGLVKKGLLPD GFEGHKEWIELSTRYRRLIEPLDISNYHRHLKNEDTGPYMLKGRPNRYKH AQRGYEHELLKAGKSSEEIEESGCGSCFWADVEELKGKPYESVEVKRFEK LVEGWITNREIDDEQIFLDGSTFTKWWRSLPEEHKRSSLLRQRMGETRST
Oilseed rape (Brassica napus L.) was formed ~7500 years ago by hybridization between B. rapa and B. oleracea, followed by chromosome doubling, a process known as allopolyploidy. Together with more ancient polyploidizations, this conferred an aggregate 72x genome multiplication since the origin of angiosperms and high gene content. We examined the B. napus genome and the consequences of its recent duplication. The constituent An and Cn subgenomes are engaged in subtle structural, functional, and epigenetic cross-talk, with abundant homeologous exchanges. Incipient gene loss and expression divergence have begun. Selection in B. napus oilseed types has accelerated the loss of glucosinolate genes, while preserving expansion of oil biosynthesis genes. These processes provide insights into allopolyploid evolution and its relationship with crop domestication and improvement.
BACKGROUND: Brassica oleracea is a valuable vegetable species that has contributed to human health and nutrition for hundreds of years and comprises multiple distinct cultivar groups with diverse morphological and phytochemical attributes. In addition to this phenotypic wealth, B. oleracea offers unique insights into polyploid evolution, as it results from multiple ancestral polyploidy events and a final Brassiceae-specific triplication event. Further, B. oleracea represents one of the diploid genomes that formed the economically important allopolyploid oilseed, Brassica napus. A deeper understanding of B. oleracea genome architecture provides a foundation for crop improvement strategies throughout the Brassica genus. RESULTS: We generate an assembly representing 75% of the predicted B. oleracea genome using a hybrid Illumina/Roche 454 approach. Two dense genetic maps are generated to anchor almost 92% of the assembled scaffolds to nine pseudo-chromosomes. Over 50,000 genes are annotated and 40% of the genome predicted to be repetitive, thus contributing to the increased genome size of B. oleracea compared to its close relative B. rapa. A snapshot of both the leaf transcriptome and methylome allows comparisons to be made across the triplicated sub-genomes, which resulted from the most recent Brassiceae-specific polyploidy event. CONCLUSIONS: Differential expression of the triplicated syntelogs and cytosine methylation levels across the sub-genomes suggest residual marks of the genome dominance that led to the current genome architecture. Although cytosine methylation does not correlate with individual gene dominance, the independent methylation patterns of triplicated copies suggest epigenetic mechanisms play a role in the functional diversification of duplicate genes.
