Joan A. Steitz, Ph.D., internationally renowned for her contributions to the field of molecular genetics, has been named Sterling Professor of Molecular Biophysics and Biochemistry by vote of the Yale Corporation.

Dr. Steitz’s studies have defined the roles of small nuclear ribonucleoprotein particles in RNA processing in mammals. She has focused her research on the structure and function of these cellular complexes, which play a key role in some of the most basic biological processes that convert information in the DNA to the active protein molecules of the living cell. She discovered the important roles that cellular particles known as small nuclear ribonucleoproteins, or snurps, play in the activity of cells. In addition to providing new understandings of the mechanics of gene expression, Dr. Steitz’s research also has implications for improved diagnosis and treatment of autoimmune diseases, particularly rheumatic diseases that occur when a person’s own antibodies attack snurps.

A member of the Yale faculty since 1970 and chair of her department, Dr. Steitz has led the molecular genetics program in the Boyer Center for Molecular Medicine and is also an investigator with the Howard Hughes Medical Institute. Prior to her Yale appointment, she did postdoctoral work at the Medical Research Council Laboratory of Molecular Biology in Cambridge, England, where she worked with Nobel laureate Francis Crick. She earned her B.S. in chemistry from Antioch College and her Ph.D. from Harvard University, where she worked with another Nobel laureate, James D. Watson. Drs. Watson and Crick elucidated the structure of DNA, the genetic material of living organisms.

Dr. Steitz was appointed a full professor at Yale in 1978 and became the Henry Ford II Professor of Molecular Biophysics and Biochemistry in 1992. At Yale, she established a laboratory dedicated to the study of RNA structure and function. Dr. Steitz’s achievements have earned her many honors, including the National Medal of Science and the Christopher Columbus Discovery Award in Biomedical Research. She was the first woman to win the Warren Triennial Prize, which is often described as the “Nobel Prize predictor” because so many of its recipients have gone on to win the latter award, and was also the first woman to be presented Israel’s Weizmann Women & Science Award. Steitz is a member of the American Academy of Arts and Sciences and the National Academy of Sciences.

Paul B. Sigler, M.D., Ph.D., a specialist on the chemical mechanisms in cell regulatory processes, has been named the Henry Ford II Professor of Molecular Biophysics and Biochemistry by vote of the Yale Corporation.

Dr. Sigler is engaged in the study of two cell regulatory processes, controlled gene expression and transmembrane signaling. Specifically, he has investigated the interactions of proteins and nucleic acids and how genetic code is transcribed through selective binding of regulatory proteins to target DNA sequences. In addition, he recently led a team that received national attention for visualizing in atomic detail (three-dimensional computerized “snapshots”) how two female sex hormones, progesterone and estrogen, bind to their receptors. The team was also the first to solve the structure of progesterone bound to the human receptor.

In his research, Dr. Sigler uses X-ray crystallography to determine the three-dimensional structure of molecules and how they link together. His work has also revealed for the first time how genes in cells throughout the body respond to a large family of hormones that include the adrenal and sex steroids, vitamin D, thyroid hormone and retinoic acid, which is crucial in embryonic development. Among his current projects is an analysis of the structure and function of chaperonin-assisted protein folding.

Dr. Sigler, who is also an investigator at the Howard Hughes Medical Institute, joined the Yale faculty in 1989. Prior to coming to Yale, he was a professor of molecular and theoretical biology, biophysics and biochemistry for 21 years at the University of Chicago.

A graduate of Princeton University, Dr. Sigler earned his medical degree from Columbia University in 1959 and was an intern and resident in medicine at the Columbia-Presbyterian Medical Center in New York. He received a Ph.D. in biochemistry in 1968 from the University of Cambridge’s Medical Research Council Laboratory of Molecular Biology, where he was a Helen Hay Whitney Fellow.

Dr. Sigler is the recipient of numerous honors, including a Guggenheim Fellowship, a U.S. Public Health Service Research Career Development Award and a Merit Award from the National Institute of General Medical Sciences. He is a member of the National Academy of Sciences and a fellow of the American Academy of Arts and Sciences.