Seminar – Sam Pfaff, PhD – “Characterization of the Cellular and Molecular Pathways that Underlie Spinal Motor Circuit Function”

Samuel L. Pfaff, PhD
Professor, Gene Expression Laboratory
Benjamin H. Lewis Chair in Neuroscience
The Salk Institute for Biological Studies
Lab website: pfaff.salk.edu

About the Speaker: Dr. Sam Pfaff is the Benjamin H. Lewis Chair in Neuroscience and professor in the Gene Expression Laboratory at the Salk Institute for Biological Studies. He also holds appointments with the biology and neuroscience programs at the University of California, San Diego. He received his BA in biology from Carleton College (Northfield, MN) and his PhD in molecular biology from the University of California, Berkeley. His post-doctoral training was done at Vanderbilt University with William Taylor on gene regulation followed by Columbia University with Thomas Jessell on neural development. He is the recipient of the Javits Neuroscience Investigator Award, McKnight Scholar Award, PEW Scholar Award, and an Alfred P. Sloan Research Fellow Award.

Pfaff’s lab has revealed important principles related to neural development, gene regulation, axon guidance and connectivity, and spinal motor circuit function. He is well known for characterizing one of the first examples of molecular diversification among neuronal subtypes through analyses of the combinatorial activity of the LIM homeodomain gene family in spinal neurons. He showed that LIM genes are expressed in unique combinatorial arrays that define motor neuron subtypes and interneurons (Cell 1994). Subsequent molecular-genetic studies provided a detailed structure-function analysis of the transcriptional complexes that form the LIM code (Cell 1996, Cell 1998, Nature 2000, Cell 2002, and Neuron 2003). From these studies it has become common to use genetic markers for characterizing the function of neuronal subtypes within circuits, for defining stem cell development, and for programming motor neuron identity with transcription factors. Following this work Pfaff examined motor axon guidance from the view of understanding how a small number of signaling proteins account for the enormous wiring complexity of the brain. He uncovered a variety of checkpoints that gate the activity of axon guidance ligands/receptors, thereby uncovering mechanisms that control their spatial and temporal activity (Cell 2005, Science 2008, Cell 2001, and Cell 2012). His current work focuses on characterizing spinal neural circuits that underlie motor control (Science 2021), and identification of regulatory pathways relevant to motor neuron disease (Science 2015, Nature 2015).

For Further Information, Contact: Clark Kellogg at kellogg@waisman.wisc.edu
The seminar series is funded by the John D. Wiley Conference Center Fund, the Friends of the Waisman Center and Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) grant P50HD105353.