Analysis of cycling genes using complementary high throughput datasets. (a) Number of interactions between cycling genes and nine cell cycle transcription factors. (b) Average expression level of sets of budding yeast genes in stationary phase (data from Gasch and coworkers ). (c) Expression levels of human genes in normal tissues, using data presented by Shyamsundar and colleagues  (also see Additional data file 1 [Supporting Figure 4]). Genes in the conserved set have lower expression levels for most nonproliferating normal tissues when compared with the full list and the list presented by Whitfield and coworkers . For 26 out of 36 normal tissues this difference is significant with a P value < 0.05. (d) Arabidopsis cells in developmental arrest experiments . Flower cells in the mutants stop growing after stage 11, whereas cells in the stem grow normally. Again, the conserved set is expressed at lower levels in developmental arrest (P = 0.027 at stages 11 and 12; P = 0.003 at stages 13 and 14). (e) Expression data from studying sexual differentiation and mating in fission yeast .
Lu et al. Genome Biology 2007 8:R146 doi:10.1186/gb-2007-8-7-r146