Stem cell therapy have great potentials in clinical application. ES cells represent an unlimited source to generate all different types of adult stem cells. However, the events during the differentiation of ES cells into adult stem cells are unclear, although it is thought that epigenetic events are critical for this process. We plan to study the chromatin binding proteins in ES cells. Chromatin binding proteins are proteins which are critical for regulating the epigenetic events. Therefore, this project will provide molecular insights into the differentiation process of ES cells and faciliate the clinical utilization of ES cells.