Maruyama et al. BMC Genomics 2010, 11:363 http://www.biomedcentral.com/1471-2164/11/363 4.0 [44]). Node support of each clade was evaluated using bootstrap analysis (1000 replicates). Accession numbers All sequences are deposited in dbEST (Expresses Sequence Tags database) of GenBank (NCBI). SGFAc: gi 224366827 - gi 224366849; SGFRm: gi 224366850 - gi 224366907 and SGFRs: gi 224366908 - gi 224366954. Additional material Additional file 1 Biological categories for GRP contigs obtained from Gene Ontology. Assignment of Gene Ontology (GO) biological process terms to the glycine-rich proteins from libraries of female salivary glands of A. cajennense, R. sanguineus and R. microplus ticks. Additional file 2 Comparison between sequences of R. microplus ticks and Nephila spiders. Multiple alignment of glycine-rich proteins R. microplus ticks from Clade 1 (Figure 2) and flagelliform silk proteins from Nephila genus obtained from GenBank [acession numbers: Nc-FSP871 (AAC38846.1), Nm-FSP1884 (AAF36091.1) and Nc-FSP2249 (AAF36090.1)]. Additional file 3 Comparison between sequences of A. cajennense ticks and Kukulcania spiders. Multiple alignment of glycine-rich proteins of A. cajennense ticks from Clade 2 (Figure 2) and major ampullate spidroin from Kukulcania genus obtained from GenBank [accession numbers Kh- Masp2.1 (AAT08434.1) and Kh-Masp2.2 ( AAT08435.1)]. Abbreviations SGF: stands for salivary glands of female ticks; Rm: for Rhipicephalus (Boophilus) microplus; Rs: for Rhipicephalus sanguineus; Ac: Amblyomma cajennense. Thus, the abbreviations SGFRs, SGFRm and SGFAc mean, respectively, cDNA library of salivary glands from feeding female ticks of Rhipicephalus sanguineus, Rhipi- cephalus (Boophilus) microplus and Amblyomma cajennense. Authors' contributions SRM and EA constructed the libraries, performed the bioinformatic treatment of the sequences, performed the analyses, including phylogenetic and statisti- cal analyses, and drafted the manuscript; JMA assisted with the bioinformatic treatment of the sequences, the analyses and preparation of the manuscript; JMR assisted with the bioinformatic treatment of the sequences and analyses; JGV assisted with the strategy of library construction, LGB and GRG con- structed the libraries; SP, RB and MPJS assisted in the analyses; BRF and IKFMS participated in the study's coordination and drafted the manuscript; IKFMS conceived the study. All authors read and approved the final manuscript. Acknowledgements This work was supported by grants from the Conselho Nacional de Desenvolvi- mento Científico e Tecnológico - CNPq (grant numbers 420067/2005-1 and 505810/2004-2), and the Fundação de Amparo à Pesquisa do Estado de São Paulo - FAPESP (04/09992-7) and by the Intramural Research Program of the National Institute of Allergy and Infectious Diseases. The authors thank Dr. João S. Silva for generous and continuing support of this work performed in his lab- oratory. This work fulfils part of the requirements for a MSc program for S.R.M, supported by scholarships from FAPESP (06/54041-6 and 07/59357-4). Author Details 1Departament of Biochemistry and Immunology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP 14049-900, Brazil, 2Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-8132, USA, 3Departament of Maternal and Child and Public Health Nursing, Ribeirão Preto School of Nursing, University of São Paulo, Ribeirão Preto, SP 14049-900, Brazil, 4School of Veterinary Medicine, Federal University of Uberlândia, Uberlândia MG 38400-902, Brazil, 5International Livestock Research Institute, Nairobi, Kenya, 6Embrapa Recursos Genéticos e Biotecnologia, 70770-900, Brasília, DF, Brazil and 7Universidade Paulista, Avenida Baguaçu, 1939, 16018- 280 - Araçatuba, SP - Brasil Received: 14 December 2009 Accepted: 8 June 2010 Published: 8 June 2010 TB©hM2isC0ia1Gsr0etaiMncoleaOmripusceyasnv2mAa0icl1a0eb,tsle1a1lfa;r:lo3itc6me3ln:ehsdetiesptB:r/ibowuMwtewd.bCuieondmtreadtlhcLetdn.etraml.csomft/h1e47C1re-2a1ti6v4e/C11o/m36m3onsAt ributionLicense(ht p:/ creativecommons.org/licenses/by/2.0),whichpermitsunrestricteduse,distribution,andreproductioninanymedium,providedtheoriginalworkisproperlycited. 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