The Modular Organization Of protein-protein Interaction Networks Of Unicellular Eukaryotes

ZAMPONI N. ; PEROTTI J.I.; MIRAS S.L., ; FELIZIANI C.; TAMARIT F.; TOUZ M.C.

Congreso; 47th Annual Meeting. Argentine Society for Biochemistry and Molecular Biology Research.; 2011

Network theory provides a framework to analyze, from atopological point of view, large amounts of data regarding molecularinteractions and provide an integrated view of cellular function andevolution. In the past decades, complex network approaches to celland molecular biology have been crucial to reveal the underlyingarchitecture of organismal complexity. Among all of the topologicalproperties that can be extracted, modularity (the tendency ofelements or links to form more connected subsets) is considered tobe one of the main organizing principles in biological networks. Ithas been suggested, for example, that the modularity of bacterialmetabolic networks had experimented a reduction during evolution.It has been also pointed out that modularity is reduced in simbiontbacteria, but the opposite is true for obligate mammalian pathogens.In addition, the diameter of metabolic networks of parasiticeukaryotes tends to be similar to those of free-living eukaryotes,suggesting that network integrity had been a structural constraintduring evolution. In this work we compare protein-proteininteraction networks of unicellular eukaryotes extracted fromSTRING database, by calculating two different modularities. At firstglance, parasitic/early divergent unicellular organisms tend to havehigh modularity values than non-parasitic/more derived ones.