National Institute of
General Medical Sciences

Stetten Lecture videocast

For nearly 30 years, Dr. James A. Spudich has examined the molecular basis of movement. He is interested in cell motility, division, and muscle contraction. In other words, he seeks to understand what makes life go.

Spudich, a professor of biochemistry and developmental biology at Stanford University School of Medicine, is the featured speaker for this year's DeWitt Stetten Jr. Lecture, sponsored by the National Institute of General Medical Science (NIGMS). The lecture, which is part of the NIH Director's Wednesday Afternoon Lecture Series, is entitled "Single-Molecule Biomechanics and the Myosin Family of Molecular Motors." It will be held on Wednesday, October 20 at 3:00 p.m. in Masur Auditorium of the Warren Grant Magnuson Clinical Center (Building 10) on the National Institutes of Health (NIH) campus.

Spudich's group focuses its attention on myosin, a protein motor that generates mechanical force and movement by harnessing the energy of ATP. To study myosin's mode of action, the researchers use two experimental systems: mammalian muscle and the slime mold Dictyostelium. Each system enables them to examine different aspects of myosin's functioning.

Skeletal muscle is the most highly organized contractile apparatus of any cell type. To study muscle contraction at a molecular level, Spudich's group developed in vitro assays for ATP-dependent movement of purified myosin on actin filaments. He is able to observe the interaction of individual molecules of actin and myosin using an optical tweezer (laser trap) technique developed in collaboration with Nobel laureate Dr. Steven Chu.

But most of Spudich's work is done using the slime mold Dictyostelium, a soil amoeba that is an expert shape-shifter. The slime mold can exist as a single-celled organism; a motile, multicellular, slug-like creature; or a globular mass of spores supported by a long, slender stalk. It also exhibits all the behavior of nonmuscle mammalian cells. By studying Dictyostelium, Spudich was able to provide genetic proof that myosin is required for cell morphogenesis and cytokinesis.

Dr. Spudich has published more than 180 articles in scientific journals and has served as editor on a number of these journals. His most recent article, entitled "Myosin-V is a processive actin-based motor," was published in the August 5, 1999 issue of the journal Nature. He is currently associate editor of Molecular Biology of the Cell, and he has edited the Annual Review of Cell and Developmental Biology since its inception in 1994.

He is a member of several scientific societies, including the National Academy of Sciences.

Most recently, he was appointed to lead Stanford's new Bio-X interdisciplinary initiative, which is designed to "foster the coming together of leading-edge research in basic, applied, and clinical sciences to enable tomorrow's discoveries and technological advances across the full spectrum from molecules to organisms."

NIGMS sponsors the Stetten Lectures to honor Dr. DeWitt Stetten Jr., who directed the Institute from 1970 to 1974. Dr. Stetten had a strong commitment to basic research, especially in the areas of genetics, cellular and molecular biology, and chemistry. The lecture series is in its 18th year.

NIGMS is regarded as the "basic science institute" of NIH because it focuses its grant support on fundamental, non-disease-targeted investigations in the biomedical sciences. Such basic research contributes new information and concepts that can improve the diagnosis, treatment, and prevention of human disease. NIGMS' programs encompass the disciplines of cell biology, biophysics, genetics, developmental biology, pharmacology, physiology, biological chemistry, and minority biomedical research and training.

NIGMS has supported Spudich's research since 1977.