Relating Gene Expression Data on Two-Component Systems to Functional Annotations in Escherichia coli
June 28th, 2008 | by admin |Relating Gene Expression Data on Two-Component Systems to Functional Annotations in Escherichia coli.
ABSTRACT: BACKGROUND: Obtaining physiological insights from microarray experiments requires computational techniques that relate gene expression data to functional information. Traditionally, this has been done in two consecutive steps. The first step identifies important genes through clustering or statistical techniques, while the second step assigns biological functions to the identified groups. For individual microarray experiments, techniques have been developed that identify such relationships in a single step. RESULTS: We have developed an algorithm that relates patterns of gene expression in a set of microarray experiments to functional groups in one step. The effectiveness of the algorithm is demonstrated as part of a study of regulation by two-component systems in Escherichia coli. The significance of the relationships between expression data and functional annotations is evaluated based on density histograms that are constructed using product similarity among expression vectors. We present a biological analysis of three of the resulting functional groups of proteins and develop hypotheses for further biological studies. CONCLUSIONS: Our new algorithm is able to find interesting and biologically meaningful relationships, not found by other algorithms, in previously analyzed data sets. Scaling of the algorithm to large data sets can be achieved based on a theoretical model.
Denton AM, Wu J, Townsend MK, Sule P, Pruess BM.