Table 6

Gene Ontology (GO) classification ofDrosophila gene products. Each of the 14,113 predicted transcripts was searched by BLAST against a database of proteins from fly, yeast, and mouse that had been assigned manually to a function and/or process category in the GO system. Function categories were reviewed manually, and in many cases a Drosophila protein was assigned to a different category upon careful inspection. The number of transcripts assigned to each process category is the result of computational searches only. For functions, the number of transcripts assigned and manually reviewed in each category is shown (with the results of the computational search in parentheses). Certain cases illustrate the value of the manual inspection. For example, motor proteins initially included many coiled-coil domain proteins incorrectly assigned to this category by the computational search. Supplemental data are available atwww.celera.com.

Function Number of transcripts Process Number of transcripts
Nucleic acid binding 1387  (1370)Cell growth and maintenance 3894
DNA binding 919 (652) Metabolism 2274
DNA repair protein 65 (30) Carbohydrate metabolism 53
DNA replication factor 38 (18) Energy pathways69
Transcription factor 694 (418) Electron transport 8
RNA binding 259 (205) Nucleotide and nucleic acid metabolism 1078
Ribosomal protein 128 (116) DNA metabolism64
Translation factor 69 (68) DNA replication 57
Transcription factor binding 21 (116) DNA repair 110
Cell cycle regulator 52 (104) DNA packaging 112
Chaperone 159 (158) Transcription 735
Motor protein 98 (373) Amino acid and derivative metabolism 69
Actin binding 93 (64) Protein metabolism 685
Defense/immunity protein 47 (41) Protein biosynthesis 215
Enzyme 2422  (2021) Protein folding 52
Peptidase 468 (456) Protein modification 273
Endopeptidase378 (387) Proteolysis and peptidolysis 81
Protein kinase 236 (307) Protein targeting51
Protein phosphatase 93 (93) Lipid metabolism 111
Enzyme activator 9 (19) Monocarbon compound metabolism 6
Enzyme inhibitor 68 (92) Coenzymes and prosthetic group metabolism 23
Apoptosis inhibitor 15 (17) Transport 336
Signal transduction 622 (554) Ion transport 72
Receptor 337 (336) Small molecule transport 109
Transmembrane receptor 261 (280) Mitochondrial transport 43
G protein–linked receptor 163 (160) Ion homeostasis 8
Olfactory receptor 48 (49) Intracellular protein traffic 116
Storage protein12 (27) Cell death 50
Cell adhesion 216 (271) Cell motility 9
Structural protein303 (302) Stress response 223
Cytoskeletal structural protein 106 (54) Defense (immune) response149
Transporter 665 (517) Organelle organization and biogenesis 417
Ion channel 148 (188) Mitochondrion organization and biogenesis 5
Neurotransmitter transporter 33 (18) Cytoskeleton organization and biogenesis 390
Ligand binding or carrier 327 (391) Cytoplasm organization and biogenesis 7
Electron transfer 124 (117) Cell cycle 211
Cytochrome P450 88 (84)Cell communication530
Ubiquitin 11 (17) Cell adhesion 228
Tumor suppressor 10 (5) Signal transduction 279
Function unknown/unclassified 7576  (7654) Developmental processes486
Conserved hypothetical   (1474) Sex determination 7
Physiological processes 201
Sensory perception 64
Behavior54
Process unknown/unclassified 8884