Jesse Farnham will present his preFPO on Friday April 12 at 9AM in Room 302 (note room!). The members of his committee are: Mona Singh, advisor; Olga Troyanskaya and Andrea LaPaugh, readers; Vivek Pai and Tom Funkhouser, nonreaders. Everyone is invited to attend his talk. His abstract follows below. --------------------------- "Organization and function acquisition in cellular networks" A main goal of biology is to understand the functional organization of organisms. In this thesis, we apply computational techniques to large, noisy biological datasets such as protein-protein interaction (PPI) networks and expression microarrays in order to elucidate principles of how genes in PPI networks acquire new functions and contribute to the overall functional organization of life. First, we investigate the functional organization of PPI networks by presenting a metric, functional insularity, that quantifies the degree to which a protein interacts with other proteins of similar function. We find high variation in insularity values, and we identify several differences between high- and low-insularity proteins. Secondly, we investigate function acquisition by human genes by identifying changes in protein-protein interactions, gene expression, and other markers of function as genes age. Our results indicate the presence of a tradeoff between modularity and connectivity in PPI network organization; furthermore, our results suggest that young genes acquire new functions gradually as they age, allowing the functional organization of the cell to evolve over time.