Howlett et al. BMC Genomics 2012, 13:211 http://www.biomedcentral.com/1471-2164/13/211 until experimental reactions had gone to completion). Each reaction was performed in triplicate. The fit-points method was used to calculate crossing points, and expres- sion of Msex\Orco normalized to rpS3 using the Roche Lightcycler 480 software version 1.5. Additional files Additional file 1: Figure S1. Predicted amino acid sequences of M. sexta OR and GR genes newly identified in this study. Genbank accession numbers are given at the beginning of each file name. Additional file 2: Figure S2. Amino acid sequences used as BLAST queries to identify putative M. sexta OR, GR, OBP and CSP sequences. Additional file 3: Table S1. Relative expression of Msex\Orco/RPS3 measured 3 days after dsRNA treatment. Quantitative PCR data from 10 paired trials are shown; these data are graphed in Figure 4. The SEM was calculated from triplicate measurements of each sample. Competing interests The authors declare that they have no competing interests. Authors’ contributions This study was conceived of by BM, JIG and JHM, and experimental design was performed by BM, JHM, JIG, NH and KLD. Gene identification was performed by NH and BM, with contributions from KLD, EB, CG, FI, DI, and SS. Verification of selected genes by PCR was performed by NH, KLD and AS, with contributions from DI, AA, MB, RB, MB, BD, AE, QF, KH, AH, DK, SL, SM, PP, DR, AR, KR and AT. RNAi analysis was performed by KLD, AS and JHM. The manuscript was written by JHM and BM. All authors read and approved the final manuscript. Acknowledgements We thank Hugh Robertson for advice regarding transcriptome sequencing and Alvaro Hernandez and the Keck Center for Comparative and Functional Genomics at the University of Illinois Urbana-Champaign for cDNA preparation, sequencing and contig assembly. 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