Event

Bioengineering Seminar Series: Thomas Blanpied

Wednesday, May 14, 2008
2:00 p.m.-3:00 p.m.
0408 Animal Science/Agriculture Engineering Bldg.
Professor Helim Aranda-Espinoza
(301) 405-8250
helim@umd.edu

Dynamic Organization and Mobility of Actin and Scaffolds at Living Synapses

Presented by Thomas Blanpied
University of Maryland School of Medicine

Activity-regulated changes in synapse function lie at the heart of molecular theories of learning and neural development, and are the target of diseases and disorders including Alzheimer’s Disease, schizophrenia, and epilepsy. At excitatory synapses, the postsynaptic density (PSD) positions neurotransmitter receptors across the cleft from sites of neurotransmitter release, and links postsynaptic receptors with the actin cytoskeleton and intracellular signaling cascades. The size and shape of individual PSDs varies widely but correlates tightly with synapse function, and so determining the internal architecture that controls PSD organization is particularly important. However, it remains unknown to what extent individual PSDs are structurally plastic, or what underlies the variation in PSD size, shape, and organization. To pursue these fundamental questions, we are using high-resolution, live-cell imaging to examine structural plasticity within individual synapses and to directly probe the movement of scaffold proteins within single PSDs. To our surprise, single PSDs undergo continuous, actin-dependent morphological plasticity. Accordingly, to enable a more thorough understanding of actin’s diverse roles at and around the synapse, we are in addition pursuing a detailed examination of the spatial dynamics of actin organization within single spines. We hope that the answers provided by these experiments will provide novel and direct insight to how the synapse is built, maintained, and modified, and provide a uniquely powerful platform for evaluating the role and timing of particular protein-protein interactions during synaptic plasticity.

Please note the date has been changed to May 14.

Audience: Graduate  Faculty  Post-Docs