In silico Northern blot, an automated method to determine expression patterns from EST databases, reveals tissue specificity of murine 17beta-hydroxysteroid dehydrogenase type 11

In this study, we developed an automated in silico Northern blot (ISNB) for analysis of gene expression patterns from EST databases. This kind of analysis can facilitate initial enzyme characterization by providing tissue distribution patterns. For proof of principle, we analyzed the expression pattern of well-characterized murine 17beta-hydroxysteroid dehydrogenases type 1 and 4. Less characterized murine 17beta-hydroxysteroid dehydrogenase type 11 (Dhrs 8) also was included and processed bioinformatically (ISNB) and further analyzed by Northern blot. The 17beta-hydroxysteroid dehydrogenase type 11 showed the same wide expression pattern by in silico and by wet laboratory approaches. The data point to its involvement of the enzyme in lipid metabolism. The quality of the ISNB relies on the quality of EST-databases. However, our approach is an easy and versatile tool of potentially universal application.