Physiology and Biophysics

Seminars

Nov
17
Thu
2016
Lamport Lecture – Robert Lefkowitz @ HSB T-625
Nov 17 @ 4:00 pm – 5:00 pm

“Seven Transmembrane Receptors”

Robert J. Lefkowitz, MD

James B. Duke Professor of Medicine

Investigator, Howard Hughes Medical Institute

Duke University Medical Center

Seven transmembrane receptors (7TMRs), also known as G protein coupled receptors (GPCRs) represent by far the largest, most versatile, and most ubiquitous of the several families of plasma membrane receptors. They regulate virtually all known physiological processes in humans. As recently as 40 years ago, the very existence of cellular receptors for drugs and hormones was highly controversial, and there was essentially no direct means of studying these putative molecules. Today, the family of GPCRs is known to number approximately 1,000, and crystal structures have recently been solved of approximately 25 members of the family and even of a receptor-G protein complex. In my lecture, I will briefly review how the field has evolved over the past 40 years, hanging some of the story on my own research throughout this period. Then I will discuss recent developments in the field, which are changing our concepts of how the receptors function and are regulated in fundamental ways. These include the duality of signaling through G-proteins and β-arrestins; the development of “biased ligands”; and the possibility of leveraging this new mechanistic and molecular information to develop new classes of therapeutic agents. Finally, I will discuss recent biophysical and structural studies of receptor-barrestin interactions.

Apr
6
Thu
2017
2017 Hille Lecture – Thomas Schwarz @ Foege Auditorium
Apr 6 @ 4:00 pm – 5:00 pm

Moving and Removing Axonal Mitochondria

Thomas L. Schwarz, PhD
Professor Neurology
F.M. Kirby Center for Neurobiology
Children’s Hospital, Boston
and Dept. of Neurobiology, Harvard Medical School

Time: 4:00PM

Location: Foege Auditorium, GNOM S060

seminar abstract: Mitochondria are dynamic organelles.  In every cell they move and undergo fission and fusion.  Their distribution and associations with the cytoskeleton change in response to many signals, including the mitotic cell cycle.  In addition, because neurons look like no other cell in the organism, with axons of up to a meter in humans, mitochondrial motility is particularly crucial to the survival of the neuron. The neuron also needs to clear away damaged mitochondria efficiently wherever in the cell they may arise.  Not surprisingly then, defects in the transport machinery of neurons and in their mechanisms for removing damaged mitochondria have been linked to several neurodegenerative diseases, including ALS and Parkinson’s disease.  This talk will present the evidence for a motor/adaptor complex that is responsible for and regulates the movement of mitochondria and will discuss how that movement is regulated by the cell cycle, Ca++, and glucose.  We will look at the operation of two proteins PINK1 and Parkin that are mutated in forms of Parkinson’s disease and examine how these proteins operate in axons to clear away damaged mitochondria that might otherwise compromise the health of the cell.  Particularly in the case of mitophagy, we will consider the special challenges posed for neurons by their extended geometry and the difficulty of having a PINK1-dependent pathway operating far from the soma.

 

Jun
20
Tue
2017
2017 Crill Lecture – William Bialek @ D-209 HSB
Jun 20 @ 4:00 pm – 5:00 pm

Thinking about a thousand neurons

William Bialek
John Archibald Wheeler/Battelle Professor in Physics
Princeton University

Sep
21
Thu
2017
PBIO Seminar Series: Andrei Smertenko @ HSB G-328
Sep 21 @ 9:30 am – 10:30 am

How plants conquer the space: the cell’s flying plates

Plant cytokinesis is orchestrated by a specialized structure, the phragmoplast. The phragmoplast first occurred in representatives of Charophyte algae and then became the main division apparatus in land plants.  Major cellular activities, including cytoskeletal dynamics, vesicle trafficking, membrane assembly, and cell wall biosynthesis, cooperate in the phragmoplast under the guidance of a complex signaling network. My research focuses on the self-organization processes that govern phragmoplast functions. I will give a general overview of plant cytokinesis, and present our recent data on the gamma-tubulin independent microtubule nucleation by the plant-specific protein MACERATOR and a conserved member of TPX2 protein family.

Andrei Smertenko, Ph.D.
Assistant Professor, Molecular Plant Sciences
Washington State University

host: Linda Wordeman

Oct
12
Thu
2017
PBIO Seminar Series: Liangyi Chen @ HSB G-328
Oct 12 @ 9:30 am – 10:30 am

High spatiotemporal resolution, three-dimension fluorescence imaging of biological samples in vivo

Dr. Liangyi Chen
Professor
Laboratory of Cell Secretion and Metabolism
Institute of Molecular Medicine,
Peking University, Beijing, China

Host: Bertil Hille

Abstract: I will give two stories. (i) One story describes unpublished ultrasensitive Hessian structured illumination microscopy that enables ultrafast and long-term super-resolution (SR) live-cell imaging. At a photon dose one order less than point-scanning microscopy, Hessian-SIM has achieved 88-nm and 188-Hz spatial-temporal resolution for live cells imaging and lasted thousands of images without artifacts. Operating at 1 Hz, Hessian-SIM enables hour-long, time-lapse SR imaging with mitigatable photobleaching, highlighting the possibility of achieving SR imaging with commonly used fluorophores for an unlimited period of time. (ii) The second story is our recent Nature Methods paper, our invention of the fast high-resolution miniature two-photon microscope for brain imaging in freely-behaving mice at the single-spine level. With a headpiece weighing 2.15 g and a new type of hollow-core photonic crystal
fiber to deliver 920-nm femtosecond laser pulses, the mini-microscope is capable of imaging commonly used biosensors at high spatiotemporal resolution (0.64 μm laterally and 3.35 μm axially, 40 Hz at 256 × 256 pixels). It compares favorably with benchtop two-photon microscopy and miniature wide-field fluorescence microscopy in the structural and functional imaging of Thy1-GFP- or GCaMP6f-labeled neurons. Further, we demonstrate its unique application and robustness with hour-long recording of neuronal activities down to the level of spines in mice experiencing vigorous body and head movements or engaging in social interaction.

Oct
26
Thu
2017
PBIO Seminar Series: Brian Kalmbach @ HSB G-328
Oct 26 @ 9:30 am – 10:30 am

“Of Mice and Men: Intrinsic Membrane Properties of Human Cortical Pyramidal Neurons”

Brian Kalmbach, Ph.D.

Allen Institute for Brain Science

host: Nikolai Dembrow

Nov
2
Thu
2017
2017 Lamport Lecture – Gilles Laurent @ T-739 HSB
Nov 2 @ 4:00 pm – 5:00 pm

Evolution and brain computation

I will introduce our work towards identifying principles of brain function and computation, focused on using comparative approaches and exploiting unusual model systems (reptiles, cephalopods) to study sleep, texture perception and cerebral cortex evolution.

Gilles Laurent, PhD, DVM

Director

Max Planck Institute for Brain Research

http://www.brain.mpg.de/home/

 

4:00 PM

Location: T-739, HSB

 

host: Stan Froehner

Dec
7
Thu
2017
PBIO Seminar Series: Nikolai Dembrow @ HSB G-328
Dec 7 @ 9:30 am – 10:30 am

Title: TBA

Nikolai Dembrow, PhD

host: Stan Froehner

Jan
9
Tue
2018
PBIO Seminar: Rishidev Chaudhuri @ HSB G-328
Jan 9 @ 9:30 am – 10:30 am

“Cognitive manifolds and their dynamics across states and areas”

Rishidev Chaudhuri, PhD.
Center for Learning & Memory
The University of Texas at Austin

Host: Stanley C. Froehner

Jan
16
Tue
2018
PBIO Seminar: Ashok Litwin-Kumar, PhD @ HSB G-328
Jan 16 @ 9:30 am – 10:30 am

“Randomness and structure in neural representations for learning”

Ashok Litwin-Kumar, PhD
Center for Theoretical Neuroscience
Columbia University

Host: Stanley C. Froehner

Jan
25
Thu
2018
Canceled – Seminar: Amy Bastian, PhD @ HSB G-328
Jan 25 @ 9:30 am – 10:30 am

Canceled

Dr. Bastian’s seminar will be rescheduled for a later date.

 

 

Learning and Relearning Movement

Human motor learning depends on a suite of brain mechanisms that are driven by different signals and operate on timescales ranging from minutes to years. Understanding these processes requires identifying how new movement patterns are normally acquired, retained, and generalized, as well as the effects of distinct brain lesions. The lecture focuses on normal and abnormal motor learning and how we can use this information to improve rehabilitation for individuals with neurological damage

Amy Bastian, Ph.D.
Professor of Neuroscience
Johns Hopkins University

 

Host: John Tuthill

 

Feb
1
Thu
2018
PBIO Seminar: Julijana Gjorgieva, PhD @ HSB G-328
Feb 1 @ 9:30 am – 10:30 am

Organizing principles in developing networks and sensory populations

Julijana Gjorgieva, PhD
Research Group Leader,
Max Planck Institute for Brain Research
Assistant Professor for Computational Neuroscience,
Technical University of Munich

Host: Stanley C. Froehner

Science in Medicine – Linda Wordeman @ D-209, HSB
Feb 1 @ 11:30 am – 12:30 pm

“Curious Intersection Between DNA Repair and Microtubule Dynamics”

Linda Wordeman, Ph.D
Professor
Physiology & Biophysics, UW

Dr. Linda Wordeman, Ph.D. uses high resolution live imaging to discover how changes in microtubule dynamics influence chromosome segregation and Chromosome INstability (CIN) in cancer cells. Dr. Wordeman will describe, mechanistically, how small changes in microtubule assembly dynamics promote CIN and reveal evidence for unexpected pathways, such as DNA damage repair, that may directly impact cellular mictrotubule dynamics.

Feb
5
Mon
2018
PBIO Seminar: Scott Linderman, PhD @ HSB G-328
Feb 5 @ 9:30 am – 10:30 am

Discovering Structure in Neural and Behavioral Data

Scott Linderman, PhD
Department of Statistics
Columbia University

 

Abstract:

New recording technologies are transforming neuroscience, allowing us to precisely quantify neural activity, sensory stimuli, and natural behavior.  How can we discover simplifying structure in these high-dimensional data and relate these domains to one another? I will present my work on developing statistical tools and machine learning methods to answer this question.  With two examples, I will show how we can leverage prior knowledge and theories to build models that are flexible enough to capture complex data yet interpretable enough to provide new insight. Alongside these examples, I will discuss the Bayesian inference algorithms I have developed to fit such models at the scales required by modern neuroscience.  First, I will develop models to study global brain states and recurrent dynamics in the neural activity of C. elegans.  Then, I will show how similar ideas apply to data that, on the surface, seem very different: movies of freely behaving larval zebrafish.  In both cases, these models reveal how complex patterns may arise by switching between simple states, and how state changes may be influenced by internal and external factors.  These examples illustrate a framework for harnessing recent advances in machine learning, statistics, and neuroscience.  Prior knowledge and theory serve as the main ingredients for interpretable models, machine learning methods lend additional flexibility for complex data, and new statistical inference algorithms provide the means to fit these models and discover structure in neural and behavioral data.

Host: Stanley C. Froehner

 

Feb
15
Thu
2018
PBIO Seminar Series: Bernhard Flucher @ HSB G-328
Feb 15 @ 9:30 am – 10:30 am

How and why are the currents of CaV1.1 calicum channels curtailied in skeletal muscle?

The presentation will include structure-function studies on CaV1 channels and analyses of the role of the calcium current in muscle fiber type specification and neuro-muscular junction formation using various mouse models.

Bernhard Flucher, PhD

Professor
Department of Physiology and Medical Physics
Medizinische Universität Innsbruck

host: Stan Froehner

Apr
26
Thu
2018
Bertil Hille – Distinguished Science in Medicine @ Hogness Auditorium
Apr 26 @ 12:00 pm – 1:00 pm

Distinguished Science in Medicine Lecture

Bertil Hille

Thurs., April 26, 2018

NOON

Hogness Auditorium.

May
3
Thu
2018
2018 Hille Lecture – Doris Tsao @ HSB T-747
May 3 @ 4:00 pm – 5:00 pm

Faces: a neural Rosetta stone

Objects constitute the fundamental currency of the brain: they are things that we perceive, remember, and think about.  One of the most important objects for a primate is a face. Research on the macaque face patch system in recent years has given us a remarkable window into the detailed processes underlying object recognition. I will discuss recent findings from our lab elucidating the code for facial identity used by cells in face patches. I will then discuss how this code is used by downstream areas, as well as how the brain computes what constitutes an object in the first place.

Doris Tsao

Professor of Biology
HHMI Investigator
California Institute of Technology

time: 4:00pm
location: T-747, HSB

host: Stan Froehner

May
10
Thu
2018
2018 Crill Lecture – J. Anthony Movshon @ HSB T-639
May 10 @ 2:00 pm – 3:00 pm

“Elements of visual form perception”

J. Anthony Movshon, PhD

Professor, Department of Ophthalmology

Professor, Department of Neuroscience and Physiology

Thursday, May 10, 2018
2:00 p.m.
T-639 HSB

May
17
Thu
2018
PBIO Seminar Series: Brent Doiron, Ph.D. @ HSB G-328
May 17 @ 9:30 am – 10:30 am

New Cortex.  Who dis(inhibition)?

 

Brent Doiron, PhD
Professor
Department of Mathematics
University of Pittsburgh

host: Adrienne Fairhall

seminar abstract:

New Cortex.  Who dis(inhibition)?

 

It is now clear that the inhibitory circuitry within cortical networks is very complex, with multiple cell types interacting with one another and pyramidal neurons in complicated and cell specific ways.  The theoretical community has been slow to adapt to this new circuit reality, and much of our results are obtained from analysis of simpler recurrent excitatory-inhibitory circuits. Two often cited functional roles of inhibition is to: 1) stabilize the dynamics of recurrently coupled excitatory networks, and 2) enact gain control of excitatory neuron responses to a driving stimulus.  In classic excitatory-inhibitory networks mechanisms that place the network in a high gain state necessarily flirt with network instability.  We analyze how recurrent networks of pyramidal neurons (PN), parvalbumin-expressing (PV), somatostatin-expressing (SOM), and vasoactive intestinal polypeptide-expressing (VIP) interneurons compartmentalize stability and gain control through distinct inhibitory and disinhibitory pathways.  This permits a disassociation of stability and gain control in the circuit.  We further show how PC to SOM connections can be crucial in state dependent gain amplification with a simultaneous decrease of shared variability (noise correlations).  In sum, by expanding the complexity of inhibitory architecture cortical circuits can navigate distinct functional roles of inhibition through a “division of labor” with the inhibitory circuit.  This imparts a robustness to the functional operations of the circuit that is absent in the often fine-tuned reduced excitatory-inhibitory framework.

May
24
Thu
2018
PBIO Seminar Series: Ariel Rokem @ HSB G-328
May 24 @ 9:30 am – 10:30 am

seminar: T.B.A.

Ariel Rokem, PhD
Senior Data Scientist
eScience Institute, University of Washington

host: Fairhall

May
31
Thu
2018
PBIO Seminar Series: Nicholas Whitehead @ HSB G-328
May 31 @ 9:30 am – 10:30 am

Simvastatin: unexpected or logical therapy for muscular dystrophy?

Nicholas P Whitehead, Ph.D.

University of Washington

host: Stanley C. Froehner

Jun
7
Thu
2018
PBIO Seminar Series: Amy Bastian @ HSB G-328
Jun 7 @ 9:30 am – 10:30 am

Learning and Relearning Movement

Human motor learning depends on a suite of brain mechanisms that are driven by different signals and operate on timescales ranging from minutes to years. Understanding these processes requires identifying how new movement patterns are normally acquired, retained, and generalized, as well as the effects of distinct brain lesions. The lecture focuses on normal and abnormal motor learning and how we can use this information to improve rehabilitation for individuals with neurological damage

Amy Bastian, Ph.D.
Professor of Neuroscience
Johns Hopkins University

Host: John Tuthill