ession is altered in skeletal muscle with ovariectomy. We screened estradiol compared to vehicle-treated ovariectomized mice. This effect is seen as early as April ERs in Skeletal Muscle explanation for the muscle difference could be the oxidative capacity of the muscle types. The soleus is a highly oxidative muscle, containing many mitochondria. In cell culture studies of muscle cells, ERa has been found primarily localized to the mitochondria. This is in contrast to the TA and EDL which are relatively more glycolytic, and may have fewer mitochondria. Since estradiol induced Gpx time point tested. In fact, MyoD levels actually decreased,Medications exert their pharmacologic effects by interacting with a wide range of cellular components. To facilitate drug discovery and development, methods are needed to identify cellular targets and elucidate the mechanisms of action of candidate chemical compounds. Conventional drug screening approaches that focus on specific biochemical activities allow the identification of compounds that target the particular activities, but the selected compounds often have multiple in vivo targets that must be identified. Alternative approaches involve cell-based screens that account for interactions within the whole cell; however, in vivo targets must still be identified because cell-based screens focus on the desired cellular response rather than the biomolecular activity of the targets. A recent study in Saccharomyces cerevisiae used a comprehensive panel of yeast deletion mutants and microarray technology to facilitate the identification of the intracellular targets of a compound. For example, mutants that show a specific sensitivity or resistance to a candidate drug can be selected from the yeast mutant pool using a fitness-based approach combined with a yeast DNA barcode array. Alternatively, a compendium approach examining multiple cellular response parameters can be used to infer the drug targets of a novel compound based on reference bioactivity profiles of well-characterized drugs. Fluorescence microscopic imaging is advantageous for highcontent assays that NVP-BHG712 site assess in vivo drug effects using multiple cellular response parameters. To examine a number of intracellular events in Saccharomyces cerevisiae, we recently developed CalMorph, a high-throughput, high-resolution, image-processing program that allows us to analyze and quantitate April High-Content Image-Profiling identified and potentially affected cellular pathways were revealed, demonstrating the validity of this approach. Results A high-content image-profiling method To evaluate similarities between morphologic changes in drugtreated wild-type cells and mutant strains, we calculated the Pearson product-moment correlation coefficient R and the associated P value for the Hydroxyurea We used hydroxyurea as a representative of compounds that affect DNA metabolism. Hydroxyurea is used as an antitumor agent with antileukemic activity, which results from inhibition of ribonucleotide reductase activity and consequent suppression of DNA synthesis. The ribonucleotide reductases are aApril High-Content Image-Profiling April High-Content Image-Profiling Compound Hydroxyurea Concanamycin A Lovastatin Echinocandin B Concentrations Target cellular process Deoxynucleotide triphosphate synthesis Vacuolar acidification Mevalonate synthesis Target genes RNR doi: rnr Concanamycin A mutants 
were similar to the dose-dependent morphologic changes induced by concanamyci
