We determine differentially expressed genes using replicated cDNA microarrays in two experimental conditions of Bacillus Subtilis. The first experiment compares a sigma factor E mutant strain versus wildtype, and the second experiment compares cells induced with sigma factor E versus wildtype. We examine normalization methods and use a Bayesian hierarchical model introduced by Tseng et al. (2001) to determine differentially expressed genes. We compare differentially expressed genes in the mutant and induction experiments.
This is joint work with Patrick Eichenberger, Richard Losick and Jun Liu.