Network prediction of the potential molecular mechanisms in birds of prey exposed to organochlorine pesticides

In the 1960s, organochlorine compounds were responsible for the decline of birds of prey populations such as Haliaeetus leucocephalus and Falco peregrinus. Pesticides similar to DDT cause bioaccumulation in birds, affecting their eggshell composition and compromising their development. Using system biology tools, the goal of this study was to better comprehend how organochlorines act on birds. We performed a literature review, using the STITCH 5.0 platform, searching for the terms DDT and TCDD. The sub-networks were amplified in 100 interactions in STRING 10.5 and joined by the Cytoscape 3.4.0 Merge software, using the experimental animal model Gallus gallus. Clusterization, gene ontology, and centrality were the parameters evaluated in the resulting network. The resulting network had 1,417 interactions and 137 nodes. The clusterization indicated four clusters and the gene ontology pointed to biological processes related to cell signaling and morphological development. The centrality analysis indicated ESR1 and HSP90AB1 as hub/bottleneck proteins involved in the estrogen pathway and calcium transport. Therefore, it is possible that HSP90 proteins have increased expression in birds contaminated with organochlorine pesticides, favoring ESRI-organochlorines interaction and disturbing the calcium availability related to the eggshell formation. The presence or absence of heat shock proteins, such as HSP90, influences several aspects of reproduction in many species. Therefore, the relationship between the HSP90 protein expression and thin-shell syndrome was identified for the first time in this in silico study.