BMC Genomics 2009, 10:295 http://www.biomedcentral.com/1471-2164/10/295 tags. CO designed the primers for Real-time RT-PCR and BH performed the experiments. CO and RS developed the experimental strategy, and were responsible for the prep- aration of the manuscript. RS and WF participated in the coordination of the study. All authors read and approved the final manuscript. Additional material Additional file 1 490 differentially expressed genes between 23 and 35 DAP. Descrip- tion and normalized counts for 490 loci matched by LongSAGE that were differentially expressed in B. napus seeds at 23 or 35 days after pollina- tion (DAP). Click here for file [http://www.biomedcentral.com/content/supplementary/1471- 2164-10-295-S1.xls] Additional file 2 Enriched GO terms for 490 differentially expressed genes between 23 and 35 DAP. Statistically enriched Gene Ontology (GO) terms exclu- sively found for one of the time-points 23 DAP and 35 DAP of B. napus seed development (p < 0.05) for 490 differentially expressed genes calcu- lated using GOEAST (Zheng and Wang, 2008). Click here for file [http://www.biomedcentral.com/content/supplementary/1471- 2164-10-295-S2.xls] Additional file 3 All LongSAGE tags extracted from B. napus seed at 23 and 35 days after pollination (DAP) and matched via Brassica ESTs to A. thaliana genes. Description and normalized counts for all A. thaliana loci matched by LongSAGE that were expressed in B. napus seeds at 23 or 35 days after pollination (DAP) and matched in sense and/or antisense orientation. Genes are sorted by locus name. Click here for file [http://www.biomedcentral.com/content/supplementary/1471- 2164-10-295-S3.zip] Acknowledgements This work was partially supported by the German Research Foundation (DFG) grant SN14/7-2. 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