Since this prior was much greater than the background probability of other protein pairs (0.1%), we began by using the pairwise Lex-A Y2H assay48 to test all 606 predictions for which sequence-verified clones were available. Of these, 136 tested positive and 470 negative. After each 96-well plate of tests (seven plates total), the interaction probabilities were updated resulting in an increase to >99.9% for pairs testing positive and a decrease to 90.5% for pairs testing negative. Since the 136 positives now had probability greater than the upper threshold (95%), all of these could be added to the interactome map and removed from further testing.