Table 2. Gene ontology analysis.

GO.ID	Term	Annotated	Significant	Expected	p value
GO:0010584	pollen exine formation	92	44	4.73	<1e-30
GO:0009827	plant-type cell wall modification	336	46	17.26	1.20E-09
GO:0008216	spermidine metabolic process	25	10	1.28	2.00E-07
GO:0009860	pollen tube growth	393	43	20.19	2.50E-06
GO:0006527	arginine catabolic process	8	5	0.41	1.70E-05
GO:0006817	phosphate ion transport	32	9	1.64	2.30E-05
GO:0008643	carbohydrate transport	97	18	4.98	2.30E-05
GO:0046467	membrane lipid biosynthetic process	210	25	10.79	8.00E-05
GO:0006596	polyamine biosynthetic process	24	7	1.23	0.00015
GO:0016036	cellular response to phosphate starvation	194	22	9.97	0.00042
GO:0055085	transmembrane transport	1020	80	52.4	0.00048
GO:0034720	histone H3-K4 demethylation	5	3	0.26	0.00125
GO:0009396	folic acid-containing compound biosynthetic process	18	5	0.92	0.00173
GO:0030162	regulation of proteolysis	6	3	0.31	0.0024
GO:0048235	pollen sperm cell differentiation	47	8	2.41	0.00248
GO:0046938	phytochelatin biosynthetic process	7	3	0.36	0.00405
GO:0006665	sphingolipid metabolic process	88	12	4.52	0.00582
GO:0030036	actin cytoskeleton organization	254	14	13.05	0.00587
GO:0010216	maintenance of DNA methylation	15	4	0.77	0.00599
GO:0009395	phospholipid catabolic process	15	4	0.77	0.00599
GO:0010951	negative regulation of endopeptidase activity	8	3	0.41	0.00623
GO:0010199	organ boundary specification between lateral organs and meristems	8	3	0.41	0.00623
GO:0015800	acidic amino acid transport	7	3	0.36	0.00763
GO:0010084	specification of organ axis polarity	3	2	0.15	0.00764
GO:0090408	phloem nitrate loading	3	2	0.15	0.00764
GO:0042398	cellular modified amino acid biosynthetic process	84	10	4.32	0.01076
GO:0010205	photoinhibition	18	4	0.92	0.01188
GO:0009823	cytokinin catabolic process	10	3	0.51	0.01236

Biological Processes identified to be up-regulated based on 1'487 genes identified to be up-regulated in the AIC as compared to the cell types composing the mature gametophyte (egg cell, central cell, synergid cells).