Completed his PhD in 2004 at Duke University. His research aims to address several fundamental questions in stem cell biology: how the developmental potential of embryonic progenitors and adult tissue stem cells is transmitted or restricted in their progenies at the molecular level when they go through critical transitions such as cell fate specification, self-renewal of stem cells as well as stress response, and how these regulatory mechanisms go awry in aging and diseases. Answers to these questions will help to manipulate skin stem cells for regenerative medicine and discover new treatment for human skin diseases.