Ranjan Sen, Ph.D.

B and T cell differentiation share several common features. B lymphopoiesis takes place in the bone marrow where environmental cues commit multipotent cells to the B lineage. Close to the point of lineage commitment gene rearrangements are initiated at the immunoglobulin heavy chain (IgH) gene locus. Activation of the locus and subsequent V(D)J recombination is regulated in complex ways, and one of our objectives is to understand the molecular mechanisms that underlie this complexity. A parallel pathway operates in the thymus where multipotent cells commit to the T lineage. One important consequence is the activation and recombination of T cell receptor (TCR) b chain genes. The TCRb gene enhancer has been shown to be essential in this process and we have used it to probe this differentiation step.

Dr. Sen received his Ph.D., degree in chemistry from Columbia University in 1982. He made the transition to molecular biology as a postdoctoral fellow in David Baltimore's laboratory at M.I.T. and the Whitehead Institute. During this stage he developed his current interests in gene regulation. In 1987 Dr. Sen was appointed Assistant Professor in the Department of Biology and Rosenstiel Research Center at Brandies University. He earned tenure in 1991 and was promoted to Professor of Biology in 1998. He moved to his present position as Chief, Laboratory of Cellular and Molecular Biology, National Institute on Aging in 2003.