Profiling the transcriptome of Thalassiosira pseudonana under environmentally relevant growth conditions

T. pseudonana gene-specific arrays were used for differential gene expression. Seven hundred nine genes were differentially expressed by more than 2-fold (Bayesian t-test, p< 0.001) under at least one growth-limiting condition relative to nutrient-replete conditions. A striking result of the hierarchical cluster analysis was the identification of a common set of genes that were upregulated by both iron and silicon limitation, but no other treatment. Together, these two treatments accounted for about one fourth of all differentially expressed genes but almost two thirds of the differentially expressed novel genes, further emphasizing the distinctive aspects of silicon manipulation in diatoms. Keywords: silicon, stress response, cell wall, iron, temperature, carbon dioxide We analyzed 6 different sets of arrays from 6 growth conditions. Four biological replicates (=4 arrays) were used for each growth condition.