Table 1C.

Functional Enrichment of rRNA Transcription Genes Containing Only PAC, or Only mRRPE, or Both Motifs

	PAC & mRRPE	PAC but not mRRPE	MRRPE but not PAC
Number of genes  in the genome	121	246	261
Number of rRNA  transcription genes	21	18	13
P-value	7.7E-13	1.4E-2	3.3E-05

The functional enrichment score, reported as a P-value, was calculated as a cumulative hypergeometric distribution (Hughes et al. 2000; Jensen and Knudsen 2000) given 3560 functionally annotated genes in the genome. We considered genes containing both PAC and mRRPE in their promoters, genes containing PAC but not mRRPE, and genes containing mRRPE but not PAC. The first row of Table 1C shows the number of genes in the genome in each set. The second row indicates the number of genes out of the total number shown in the first row that overlap with the 91 annotated rRNA transcription-related genes.