Protein-protein networks are robust

The derivation of protein-protein interaction networks of Saccharomyces cerevisiae, C. elegans and Drosophila has recently become a popular method for understanding the biology of these organisms. Network analysis is most advanced in the budding yeast, S. cerevisiae. The network of S. cerevisiae was developed using empirical methods such as yeast two-hybrids (e.g. Ito et al. 2001), expression profiling, identification of proteins in complexes using mass spectrometry, and systematic gene disruptions (Hazbun and Fields 2001). All of these analyses have allowed yeast to be the leading system for the study of protein networks. These networks have been found to be scale-free (Han et al. 2004). Scale-free networks are organized into a system of “hubs” and “spokes” where a few nodes (hubs) have more than five interacting partners, while most nodes (spokes) have five or fewer partners. Disruption of the hubs will cause much greater network perturbation than disruption of a spoke (Han et al. 2004). Therefore, disruption of a random node (protein) is unlikely to cause a serious disruption to function of the overall network (Han et al. 2004). This is one main argument for the ability of organisms to evolve. The protein network is robust, and the organism can still function in spite of mutations.


Jackie said...

Hi, Bridge :) Got your e-mail today and checked out the blog - very nice! I'm doing protein-protein interaction studies using yeast as a model system, so this post was right up my alley. We'll have to meet up for a post-graduation celebration when we're both finished (I will graduate eventually, I promise! :) -J

Bridget said...

Hey Jackie! That is cool! I worked on this project for a semester, and managed to get scooped before we published, so this is the only place I could think of to at least put our introduction :) Hope my summary was accurate! Ans yes, here's to graduating sometime in the near future- I really hope to be done in May. I'd love to see you and celebrate!!!!!

Kierstin said...

Hey Bridet...maybe I will learn a thing or two about Proteins. Will be in Tucson next week to pick up Marie...will call...maybe coffee???? or lunch (: K