Tae Hoon Kim: Knows his boundaries

JCB • VOLUME 183 • NUMBER 1 • 2008 4 W hen and where a gene is expressed depends on its associated regulatory elements, chromatin environment, transcription factors, and numerous other infl uences that scientists do not yet fully understand. Because each gene has a particular expression pattern, it can be diffi cult to identify general rules for the switching on or off of genes. Tae Hoon Kim is not perturbed by the diffi culties. Although he started out studying regulation of one particular gene—interferon (1), he quickly got a taste for taking his regulation studies genome wide. As a postdoc with Bing Ren, Kim used ChIP on chip (Chromatin immunoprecipitation on microarrays) to map the promoters of nearly 8,000 genes in the human genome (2). He then did a similar large-scale mapping project for potential insulator elements, which form boundaries to the spread of heteroor euchromatin (3). He has also contributed to the Encyclopedia of DNA elements (ENCODE)—a project to identify all functional elements in the human genome (4). Kim now runs his own laboratory at Yale, where he is particularly concerned with investigating gene regulatory perturbations associated with cancer.