Biochemistry, Molecular Biology
Dr. Tjian was an HHMI investigator at the University of California, Berkeley from 1987 to 2009. In April 2009, he became president of HHMI. Dr. Tjian continues his research on the biochemistry of gene regulation at HHMI's Janelia Research Campus and at the University of California, Berkeley.
One of the greatest achievements of modern biology is the remarkable progress in understanding how genes work. Research by Robert Tjian has contributed substantially to this body of knowledge. Tjian studies the biochemical steps that ensure genes are turned on at the right time, and then turned off when their jobs are finished. His research has helped scientists piece together a sophisticated picture of the molecular machinery that human cells use to “decode” the genome and control the switches that turn genes on and off. This machinery is involved in every facet of human life, including embryogenesis, cellular differentiation, cell growth and development, and the initiation of disease.
Armed with a PhD degree in biochemistry and molecular biology, Tjian began his scientific career in 1976, studying how cells live and what happens when their growth goes awry. At the time, little was understood about how genes are turned on and off. “The field was wide open and promised to be of fundamental importance,” Tjian recalls.
Specifically, Tjian studies how genetic information stored in DNA is copied (transcribed) into RNA, which directs the production of proteins that are essential to life. He has devised a way to isolate individual components of the cell involved in transcription, to recreate this complex, highly regulated process in a test tube, and even to observe these reactions at single-molecule resolution. Advances in technology have also enabled Tjian and his team to purify rare sequence-specific transcription factors, which bind to DNA at specific sites and regulate gene expression, and to isolate the genes that encode these important transcription factors.
Work from Tjian’s lab has provided new insights into the molecular mechanisms that underlie various human diseases and conditions, including Huntington’s disease, cancer, diabetes, and infertility.
Tjian has also been actively involved in training new generations of molecular biologists and biochemists who are poised to answer questions generated by today’s scientists. “It gives me great pride to have guided so many students into medical careers, and to watch my students and postdoctoral fellows develop into first-rate scientists,” he says.