Sangdun Choi is currently the Chair of the Department of Biological Sciences and a Professor at the Department of Molecular Science and Technology in Ajou University, Korea. He joined the faculty of the Department of Molecular Science and Technology, Ajou University, as an Associate Professor in 2006. His research interests include Toll-like receptor signaling, innate immunity, cellular signaling and systems biology. He earned his PhD at the Texas A&M University, USA. He was one of the pioneers in the development of Bacterial Artificial Chromosomes (BACs). He was instrumental in the construction of a complete human BAC library for the Human Genome Project (HGP). He was also involved in the second consortium, Alliance for Cellular Signaling (AfCS). Furthermore, he served as the Director of the Transcription Analysis Laboratory at the California Institute of Technology (Caltech), USA. He has published more than 200 scientific articles in international journals including Nature, Science, Nature Biotechnology, Blood and Proceedings of the National Academy of Sciences. He has edited seven books including Encyclopedia of Signaling Molecules, Systems Biology for Signaling Networks and Introduction to Systems Biology. He is an academic editor of PLoS ONE and an active editor for several other international journals.