Table 2

DDI-PPI mapping: interactions involving only single-domain proteins

Organism^a

E. coli

yeast

worm

fly

human

Number of PPIs (with known domains) (N)

497

2,418

335

2,068

1,633

Number of PPIs to which DDIs could be mapped (n) (%; n/N*100)

Median value of random networks (P value)

117 (24%)

92 (0.005)

284 (12%)

79 (<0.001)

60 (18%)

38 (<0.001)

217 (10%)

55 (<0.001)

400 (25%)

135 (<0.001)

^a Organism labeling: yeast: S. cerevisiae, worm: C. elegans, fly: D. melanogaster. For the analysis of each organism, DDIs in the structural database that are based on single-domain proteins of the respective organism were excluded. DDI, domain-domain interaction; PPI, protein-protein interaction.

Itzhaki et al. Genome Biology 2006 7:R125   doi:10.1186/gb-2006-7-12-r125