BMC Genomics 2008, 9:308 Additional material Additional file 1 Homology model of the RAWUL domain from human Bmi1 protein. Click here for file [http://www.biomedcentral.com/content/supplementary/1471- 2164-9-308-S1.doc] Additional file 2 Web page with additional information at: http://www.pdg.cnb.uam.es/ RAWUL Click here for file [http://www.biomedcentral.com/content/supplementary/1471- 2164-9-308-S2.htm] Acknowledgements This work is supported by a Deutsche Forschungsgemeinschaft (DFG) grant (KO2302/8-1). ZRS is supported by a National Science Fundation (NSF) grant (IBN 0236399) and a United States Department of Agriculture (USDA) grant (03-35301-13244). DD is supported by the EU grant 3D- Repertoire (LSHG-CT-2005-5120828). We thank Kimmen Sjolander (Departments of bioengineering and Plant and Microbial Biology, University of California, Berkeley, CA, USA) for helpful suggestions of the manuscript. References 1. 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