systematic differences in signal emitting and receiving revealed by pagerank analysis of a human protein interactome信号发射和接收系统的差异揭示了pagerank interactome人类蛋白质的分析.pdf

Systematic Differences in Signal Emitting and Receiving Revealed by PageRank Analysis of a Human Protein Interactome 1. 1,2. 3 Donglei Du , Connie F. Lee , Xiu-Qing Li * 1 Quantiative Study Group, Faculty of Business Administration, University of New Brunswick, Fredericton, New Brunswick, Canada, 2 The Fu Foundation School of Engineering and Applied Science, Columbia University, New York, New York, United States of America, 3 Molecular Genetics Laboratory, Potato Research Centre, Agriculture and Agri-Food Canada, Fredericton, New Brunswick, Canada Abstract Most protein PageRank studies do not use signal flow direction information in protein interactions because this information was not readily available in large protein databases until recently. Therefore, four questions have yet to be answered: A) What is the general difference between signal emitting and receiving in a protein interactome? B) Which proteins are among the top ranked in directional ranking? C) Are high ranked proteins more evolutionarily conserved than low ranked ones? D) Do proteins with similar ranking tend to have similar subcellular locations? In this study, we address these questions using the forward, reverse, and non-directional PageRank approaches to rank an information-directional network of human proteins and study their evolutionary conservation. The forward ranking gives credit to information receivers, reverse ranking to information emitters, and non-directional ranking mainly to the number of interactions. The protein lists generated by the forward and non-directional rankings are highly correlated, but those by the reverse and non-directional rankings are not. The results suggest that the signal emitting/receiving system is characterized