Thursday, 07/19/07 Lecture:

Control of Neuronal Timing by Sodium-Activated Potassium Channels

Leonard K. Kaczmarek, Yale University School of Medicine
Introduction by Donald S. Faber

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Lecture Abstract:
The electrical properties of neurons and other excitable cells are determined in major part by the nature of the potassium channels that they express. It has been recognized over the past twenty years that there exists a family of potassium channels that are activated by intracellular sodium. We have cloned two genes Slick and Slack that encode such channels. Major roles proposed for these channels are to produce an adaptation of firing rate during repetitive neuronal stimulation, and to protect neurons from hypoxic insults. In addition, activation of these channels in the auditory brainstem improves the ability of neurons to follow rapid synaptic stimulation with high temporal precision. Both Slack and Slick channels have unusually large C-terminal cytoplasmic domains. Recent findings indicate that the large C-terminal domain of Slack interacts with Fragile X Mental Retardation Protein (FMRP), an mRNA binding protein that has been proposed to regulate local translation of a subset of neuronal proteins. Thus, in addition to their function in regulating neuronal excitability, the activation of these channels by sodium during neuronal firing may provide a mechanism for linking neuronal activity to changes in intracellular signaling pathways that control development and learning.


Friday, 07/20/07 Lecture:
Hear a Pin Drop and Smell a Rose: How the Brain Adjusts Sensitivity to Sensations
Leonard K. Kaczmarek, Yale University School of Medicine
Introduction by Janis C. Weeks

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Lecture Abstract:
Individuals vary greatly in their ability to discriminate various aspects of their sensory environment. For example, fine discriminations in the pitch of a note or in the direction from which a sound is coming are made by musicians and orchestra conductors. Wine connoisseurs and perfumers distinguish odors that seem identical to the rest of us. Nevertheless it appears that human performance on many such tasks is improved through learning and repeated exposure to these stimuli. Recent research indicates that for the brain to make such discriminations, neurons in sensory circuits have to be precisely tuned to the incoming pattern of stimulation. The electrical properties of neurons are governed by a class of proteins termed ion channels. In the auditory system, a change in the pattern of ongoing sounds produces a biochemical change that modifies the properties of ion channels. In addition, relatively short periods of exposure to specific sounds alter the levels of channel proteins in ways that may improve the ability of the brain to differentiate similar stimuli. Finally, genetic manipulations of ion channels alter the responsiveness of sensory systems, and can lead to an extraordinarily enhanced sensitivity to external events.

Dr. Leonard Kaczmarek is a Professor in the Departments of Pharmacology and Molecular and Cellular and Physiology at Yale University School of Medicine and was Chairman of the Pharmacology Department from 1989 to 1998. He attended University of London where he received a B.Sc. in Chemistry, a M.Sc. in Biochemistry from Imperial College at University of London, and a Ph.D. in Neurochemistry from the Charing Cross Hospital Medical School at the University of London. At the MBL, Dr. Kaczmarek served as the co-director of the Neurobiology Course in 1990 and 1992 to 1994. In 1991, he also served as the Director of the Molecular Neurobiology section of the MBL's Neurobiology Course. Dr. Kaczmarek belongs to several professional societies and has been awarded numerous awards and honors, including the Javits Neuroscience Investigator Award.

Donald S. Faber received his S.B. in Electrical Engineering from Massachusetts Institute of Technology and his Ph.D. in Physiology from the University at Buffalo. He was a postdoctoral fellow in Buffalo and at the Max Planck Institute for Brain Research in Frankfurt, Germany. Dr. Faber was Assistant Professor at the University of Cincinnati from 1972 to 1974. He then moved back to the University at Buffalo, where he was a member of the faculty of the School of Medicine until 1992, when he became the Chair of Neurobiology and Anatomy at MCP-Hahnemann School of Medicine. In 1999 he joined the Albert Einstein College of Medicine where he is the Florence and Irving Rubinstein Professor and Chair of Neuroscience and Director of the Rose F. Kennedy Center. Dr. Faber was a Grass Fellow at the MBL in 1969 and was an Instructor in the Neurobiology Course from 1995 to 2003, and he served as Co-Director of the course from 2000-2003. He is a member of MBL's Science Council and a Trustee of The Grass Foundation. He was elected a Fellow of the American Association for the Advancement of Science in 1999. His research program is focused on the regulation of synaptic transmission and the relations between functional properties of neurons and the control of sensorimotor behavior.

Janis C. Weeks received her B.S. in Life Sciences from Massachusetts Institute of Technology. She received her Ph.D. from the University of California, San Diego and was a postdoctoral research associate at the the University of Washington. Dr. Weeks joined the faculty of the University of Oregon in 1989, has held the rank of professor since 1995, and served as the Head of the Department of Biology from 1998 to 2001. Dr. Weeks started out at the MBL as a teaching assistant in 1978, becoming an instructor of the MBL's Neural Systems and Behavior course in 1985 and Co-Director from 1996-2000. She has served on MBL's Science Council and became President of The Grass Foundation in 2006. She is involved in many activities in Africa, including co-organizing a course inspired by Neural Systems and Behavior in South Africa in 2006.

About the Forbes Lectures:
Since 1959, the special two-part Forbes Lecture has been supported by The Grass Foundation, a private foundation that supports research and education in neuroscience. The lectures are given in honor of pioneering neurobiologist Alexander Forbes. Traditionally, the Forbes lecturer also spends several weeks at the MBL, working alongside the Grass Fellowship Program.