in silico identification of protein-protein interactions in Silkworm,Bombyx mori

The Domesticated silkworm, Bombyx mori, an economically important insect has been used as a lepidopteran molecular model nextonly to Drosophila. Compared to the genomic information in silkworm, the protein-protein interaction data are limited. Thereforeexperimentally identified PPI maps from five model organisms such as E.coli, C.elegans, D.melanogaster, H. sapiens, S. cerevisiae wereused to infer the PPI network of silkworm using the well-recognized Interlog based method. Among the 14623 silkworm proteins,7736 protein-protein interaction pairs were predicted which include 2700 unique proteins of the silkworms. Using the iPfaminteraction domains and the gene expression data, these predictions were validated. In that 625 PPI pairs of predicted networkwere associated with the iPfam domain-domain interactions and the random network has average of 9. In the gene expressionmethod, the average PCC value of the predicted network and random network was 0.29 and 0.23100±0.00042 respectively. Itreveals that the predicted PPI networks of silkworm are highly significant and reliable. This is the first PPI network for thesilkworm which will provide a framework for deciphering the cellular processes governing key metabolic pathways in thesilkworm, Bombyx mori and available at SilkPPI (http://210.212.197.30/SilkPPI/).