Daniel Chelsky, PhD, is the chief scientific officer at Caprion Inc., a company that uses technologies called mass spectrometry and multiparametric flow cytometry to discover and test biomarkers of disease and drug efficacy, drug mechanisms of action and new therapeutic targets. Previously, he served as president of BioSignal, Inc., a subsidiary of PerkinElmer focused on research and reagents related to G-protein-coupled receptors, a large group of proteins that turn on various mechanisms inside the cell. He has also held positions as senior director of biology at Pharmacopeia, a combinatorial chemistry company; director of drug discovery at Onyx Pharmaceuticals; and principal investigator at DuPont Merck Pharmaceuticals.  He received his PhD at the University of Oregon and was an American Cancer Society fellow at the University of California, Berkeley.