Table 2.

Results of over-representation analysis of gene ontologies

Gene Ontology	GO ID	Number of probes on array	Number of genes on array	Number of genes in gene cluster	Raw p-value	FDR-corrected p-value
Cluster I-Immune Function and Development
MHC class I protein binding	GO:0042288	7	7	2	0.0000	0.0561
Neurite morphogenesis	GO:0048812	62	60	3	0.0032	0.1289
Cell fate determination	GO:0001709	59	45	2	0.0106	0.1807
Cluster II-Cell Growth
Vesicle transport along actin filament	GO:0030050	181	9	2	0.0000	0.0251
SWR1 complex	GO:0000812	182	10	2	0.0000	0.0119
Cortical actin cytoskeleton	GO:0030864	183	11	2	0.0000	0.0122
Condensed nuclear chromosome	GO:0000794	13	13	2	0.0001	0.0168
Histone acetylation	GO:0016573	186	14	2	0.0001	0.0178
Actin filament	GO:0005884	187	15	2	0.0001	0.0190
Meiosis	GO:0007126	51	51	3	0.0002	0.0269
M phase of mitotic cell cycle	GO:0000087	97	96	3	0.0024	0.0779
Cluster III-Metabolism
Sterol metabolism	GO:0016125	12	12	3	0.0000	0.0001
Trypsin activity	GO:0004295	14	14	3	0.0000	0.0001
Positive regulation of protein metab.	GO:0051247	18	18	3	0.0000	0.0002
Cholesterol metabolism	GO:0008203	18	18	3	0.0000	0.0002
Cluster IV-Stress
Lytic vacuole	GO:0000323	42	42	3	0.0001	0.2378
Lysosome	GO:0005764	54	54	3	0.0004	0.3168
Response to UV	GO:0009411	6	5	1	0.0004	0.1620
Replicative cell aging	GO:0001302	5	5	1	0.0004	0.1296
Response to water deprivation	GO:0009414	5	5	1	0.0004	0.1080
Response to reactive oxygen species	GO:0000302	7	7	1	0.0008	0.1349

We tested for significant over-representation of gene ontologies of genes within a cluster compared to the total complement of genes represented on the microarray. Gene clusters were identified by hierarchical clustering of significant gene responses across stressors (see Figure 3 for cluster identification)