Sadd et al. BMC Genomics 2010, 11:110 http://www.biomedcentral.com/1471-2164/11/110 Page 3 of 9 GO Slim overview categories can be seen in Table 2, and the full GO assignments can be found as an addi- tional file (Additional file 4). Further, the same process was completed for predicted proteins in the A. mellifera and Tribolium castaneum genomes [32,39]. This allowed for a comparison to be made with the distribution of terms that we obtained for the B. terrestris unique sequences in this study. General patterns of distribution were similar between organisms, with limited exceptions where particular GO slim categories were over- or under- represented in the B. terrestris unique sequences (Table 2). Table 2 Comparison of the percentage distribution of Bombus terrestris Gene Ontology terms (overview GO slim terms) based on the reported EST library and the distribution of Gene Ontology terms for all proteins predicted in each of the Apis mellifera and Tribolium castaneum genomes GO slim term* B. terrestris A. mellifera T. castaneum Molecular function motor activity 0.4% (14) 0.9% 0.8% ligase activity 2.0% (64) 2.1% 2.0% translation regulator activity <0.1% (2) <0.1% <0.1% signal transducer activity 1.6% (52) 2.7% 3.0% † catalytic activity 11.8% (381) 10.4% 11.0% binding 57.0% (1842) 57.8% 55.8% transferase activity 9.8% (318) 8.6% 8.6% transporter activity 4.0% (131) 5.6% 6.1% † transcription regulator activity 2.5% (81) 3.3% 3.1% antioxidant activity 0.1% (3) 0.1% 0.1% lyase activity 0.7% (23) 0.7% 0.8% oxidoreductase activity 5.2% (169) 3.7% 4.8% isomerase activity 0.5% (17) 0.3% 0.3% enzyme regulator activity 2.3% (73) 2.3% 2.0% structural molecule activity 2.1% (67) 1.3% 1.6% Biological process response to stimulus 7.0% (274) 5.9% 6.8% cellular amino acid and derivative metabolic process 1.7% (66) 1.5% 1.7% behavior 2.8% (111) 2.6% 2.7% metabolic process 18.4% (718) 14.9% † 16.2% cell differentiation 5.6% (220) 7.3% 7.1% cell communication 6.1% (240) 8.1% † 8.3% † nucleobase, nucleoside, nucleotide and nucleic acid metabolic process 10.2% (400) 6.9% † 6.5% † extracellular structure organization 0.3% (10) 0.3% 0.2% multicellular organismal development 10.1% (394) 12.0% 11.8% cellular process 11.9% (467) 12.0% 11.3% membrane fusion 0.2% (8) 0.2% 0.2% transport 8.7% (342) 9.5% 9.7% regulation of biological process 14.6% (573) 16.0% 14.9% cell death 1.3% (52) 1.2% 1.4% cell motion 0.9% (37) 1.4% 1.2% Cellular component membrane 18.3% (472) 22.6% † 23.3% † cell 6.6% (171) 7.6% 8.0% intracellular 70.8% (1830) 66.0% † 63.6% † extracellular 4.3% (111) 3.7% 5.1% Actual counts appear in brackets after the percentage. Major categories of molecular function, biological process and cellular component are treated independently. * Only manually curated terms were included to improve accuracy † Also in bold. Statistically significant difference in the representation of the GO slim term between Bombus and the organism referred to in the column (p < 0.0014, Bonferroni-corrected Fisher’s exact tests)