Web of protein interactions reflects human complexity better than number of genes
Humans don’t have many more genes than fruit flies or microscopic roundworms, but the network of protein interactions in human cells is much larger and more complex, a new estimate shows.
While people have only about 20,000 genes, the proteins encoded by those genes interact in roughly 650,000 ways. That network of interactions, or “interactome,” is about 10 times larger than that of the fruit fly and three times the size of the roundworm’s interactome.
“The research is clearly quite exciting because it seems to reconcile an observation that has bugged many scientists, which is that the complexity of an organism does not relate in any simple fashion to genome size or gene number,” comments Sebastian Bonhoeffer, a theoretical biologist at the Swiss Federal Institute of Technology in Zurich.
“At least when we score on the basis of interactome size, the humans come out top” in compariso