Spring 2023
Wednesdays, 12:00 -1:00 PM
290 Hearst Memorial Mining Building
Abstract:
The central challenge in neurobiology is to understand how the brain gives rise to behavior. However, we have limited tools to query the structure of complex, naturalistic behavior of the sort generated by animals in the wild. Here I will discuss methodologies we have developed that reveal the “syllables” and “grammar” out of which mouse behavior is organized, and our application of these approaches (including closed-loop methods) to better understand the neural basis for spontaneous action. I will both review recent progress in understanding brain-behavior relationships gleaned through these methods, and discuss recent technical advances that will propel this line of research forward in the future.
Wednesday, April 19
12noon – 1:00pm
290 Hearst Mining Building
or Register for Zoom link here:
https://berkeley.zoom.us/
Jeanne Stachowiak, University of Texas, Austin
“Flexible protein networks in membrane mechanics and medicine”
Abstract:
As the gateway for cellular entry and communication, the surface of the cell holds the answers to critical questions in biology and medicine, while simultaneously providing inspiration for engineered materials and systems. In particular, biological membranes have the ability to precisely and rapidly organize themselves in an environment of staggering complexity. Thousands of distinct protein species reside on cellular membranes, yet functional lipid-protein complexes can form within seconds in response to diverse stimuli. How is this possible? The established view is that highly structured protein complexes are responsible for organizing membranes. However, our lab and others are revealing the critical role of flexible, transient protein networks in orchestrating biological events at membrane surfaces. As one example, our recent work has shown that short-lived assemblies of disordered proteins, which have liquid-like properties at bulk scale, provide an optimal catalytic platform for assembly of endocytic vesicles, which are responsible for cellular uptake of receptors, drugs, and pathogens. In particular, we found that the early initiator proteins of clathrin-mediated endocytosis form a flexible network that permits the dynamic rearrangement of proteins and lipids required for membrane budding. As the structured clathrin coat is recruited, the transient complex of initiator proteins is progressively excluded from the budding vesicle, such that it remains at the cell surface to catalyze future rounds of endocytosis. This understanding provides new insight into the optimal design of therapeutic carriers that harness endocytosis for entry into cells. Specifically, we found that therapeutic nanoparticles must bind to cellular receptors tightly enough to localize to the cell surface but not so tightly that they disrupt the dynamic protein network responsible for endocytosis. More broadly, our lab seeks to understand and mimic the ability of biological membranes to spontaneously reorganize in response to diverse cues. This remarkable capacity for self-organization, which is largely absent in man-made materials, holds great promise for the design of responsive, cell-like therapeutic systems.
Wednesday, April 26
12noon – 1:00pm
290 Hearst Mining Building
Nick Altemose, Stanford University
Don’t miss our annual Distinguished Lecture in Bioengineering on March 22 and Rising Star Lecture on February 22.
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