Physiology and Biophysics


“Surface-surfing with a few million friends: how identity information influences bacterial collective motility” – Presented by Department of Biology @ Hitchcock Hall
Apr 22 @ 12:00 pm – 1:00 pm
Dr. Karine Gibbs, Associate Professor Department of Molecular and Cellular Biology Harvard University
“Preventing Falls Among Community-Dwelling Older Adults” – Presented by Department of Oral Health Sciences @ Health Sciences Building
Apr 22 @ 12:30 pm – 1:30 pm
Elizabeth Phelan, MD, Associate Professor Medicine/Gerontology and Geriatric Medicine University of Washington
“Neuro-immune interactions in the intestine” – Presented by Department of Immunology – Immunology 573 @ South Lake Union
Apr 22 @ 3:30 pm – 4:30 pm
Daniel Mucida, PhD, Associate Professor Immunology, Virology & Immunology Laboratory of Mucosal Immunology The Rockefeller University
“A Neural Compass that combines flexibility and stability” – Presented by The Graduate Program in Neuroscience @ Health Sciences Building
Apr 22 @ 4:30 pm – 5:30 pm
Vivek Jayaraman, Ph.D. Senior Group Leader and Head of Mechanistic Cognitive Neuroscience HHMI, Janelia Research Campus
“A Bigger and Better Picture of Clinical Specimens: Light-Sheet Microscopy for Non-Destructive 3D Pathology” – Presented by The Center for Cardiovascular Biology and the Mitochondria and Metabolism Center @ South Lake Union
Apr 23 @ 9:00 am – 10:00 am
Adam Glaser, PhD, Research Associate Mechanical Engineering University of Washington
“Rod and cone phototransduction: Molecular mechanism, quantitative model, and evolution of the genes” – Presented by Department of Physiology & Biophysics @ Health Sciences Building
Apr 23 @ 9:30 am – 10:30 am
Trevor Lamb, Ph.D. Eccles Institute of Neuroscience John Curtin School of Medical Research The Australian National University
PBIO seminar series: Trevor Lamb @ G-328 H.S.B.
Apr 23 @ 9:30 am – 10:30 am
Rod and cone phototransduction:  Molecular mechanism, quantitative model, and evolution of the genes Trevor Lamb Eccles Institute of Neuroscience, John Curtin School of Medical Research The Australian National University host: Peter Detwiler   Abstract: The first part of this presentation will outline our current understanding of the molecular basis of the phototransduction cascade in vertebrate rod and cone photoreceptors.  An overview will be given of the molecules that participate in activation, shut-off, and Ca-feedback regulation of the response to light.  Activation will be described in terms of the 2‑D diffusional encounters between molecules (rhodopsin, transducin, and the phosphodiesterase PDE6).  A recent discovery of considerable importance is that the PDE6 is only activated when it has two transducins bound; thus, the binding of a single transducin has negligible effect.  As a result, activation of the PDE6 is substantially immune to spontaneous thermal activation of transducin.  This new understanding has required the development of an updated quantitative model of phototransduction.  The revised model provides new insights into: (1) the nature of the single-photon event; (2) the existence of an additional delay in the onset phase of the rod response; and (3) the recovery of rods from bright flashes, and the nature of so-called ‘dominant time constants’ of recovery. The second part of the presentation will describe how the vertebrate phototransduction cascade evolved.  Around 600–700 million years ago, a simple chordate ancestor of ours possessed ciliary photoreceptor cells that probably used a single class of opsin that linked via a G‑protein cascade to cyclic nucleotide-gated ion channels, in a cascade bearing many similarities to that in present-day cones and rods.  As in the case of many other vertebrate features, an event (strictly, a pair of events) of monumental significance was the occurrence of two rounds of whole genome duplication (2R WGD), that led in principle to a quadruplication of every gene.  I will summarize analyses of the phylogeny (in extant species) of the genes for the proteins mediating phototransduction, and I will then describe analyses of gene synteny.  The combination of these approaches provides remarkable insights into the gene duplications (and losses) that occurred, prior to 2R WGD, during 2R WGD, and subsequently, that led to the emergence of distinct isoforms for rod and cone phototransduction proteins in present-day vertebrates.      
“Uncovering emergent properties of the kinetochore and mitotic checkpoint signaling” – Presented by Department of Biochemistry @ Health Sciences Building
Apr 23 @ 10:30 am – 11:30 am
Ajit Joglekar, Ph.D. University of Michigan
“A neural compass that combines flexibility and stability” – Presented by Division of Basic Sciences @ Fred Hutchinson Cancer Research Center
Apr 23 @ 12:00 pm – 1:00 pm
Vivek Jayaraman, Ph.D., Janelia Research Campus Howard Hughes Medicine Institute, Senior Group Leader & Head of Mechanistic Cognitive Neuroscience
“Infection-Associated Cachexia – Boon or Bane?” – Presented by Fred Hutchinson Cancer Research Center @ Arnold
Apr 23 @ 1:00 pm – 2:00 pm
Dr. Andreas Bergthaler, Principal Investigator CeMM, Research Center for Molecular Medicine of the Austrian Academy of Science Vienna, Austria
2019 Hille Lecture – Bernardo Sabatini @ T-435, HSB
Apr 24 @ 11:30 am – 12:30 pm

“New twists on old synapses – multitransmitter neurons in the mammalian brain”

Bernardo Sabatini

Alice and Rodman W. Moorhead III Professor of Neurobiology, Harvard Medical School   time: 11:30Am location: T – 435

host: Stan Froehner

Seminar Abstract: Neurons communicate via the release of neurotransmitters at synapses. It has been generally assumed that neurons in the mammalian brain utilize a single fast acting neurotransmitter and release the same substance at all of its synapses. I will present data from our laboratory and others that demonstrate a much higher complexity to neurotransmission. In older brain regions, such as the basal ganglia, many neurons release multiple small molecule neurotransmitters, such as GABA, glutamate, dopamine and acetylcholine, often targeting different cells with different transmitters. We find that in different classes of neurons, the release of collections of neurotransmitters serves different purpose, in some circuits acting as a substrate for plasticity and in others triggering cascades of synaptic signaling that evolve broad time scales. I will conclude by speculating about the contributions of multitransmitter neurons to the function of mammalian cortex and basal ganglia during learning .
“Genomic regulatory codes and circuits orchestrating immune cell fates” – Presented by Department of Bioengineering Seminar Series @ Foege
Apr 25 @ 12:30 pm – 1:30 pm
Harinder Singh, Ph.D., Professor and Director Center for Systems Immunology University of Pittsburgh
“Understanding the mechanisms of PIP2 resynthesis” – Presented by Department of Physiology & Biophysics – PBIO 519 Postdoc Lectures @ Health Sciences Building
Apr 25 @ 1:00 pm – 2:00 pm
Jongyun Myeong, PhD Senior Fellow Department of Physiology & Biophysics Dr. Bertil Hille’s Lab
“Taking the leap: Bootstrapping a startup in the genomics market” – Bioscience Careers Seminar Series @ Health Sciences Building
Apr 25 @ 5:00 pm – 6:00 pm
Ivan Liachko, PhD. Co-founder, CEO, and Chief Scientist Phase Genomics, Seattle, WA
PBIO seminar series: Colleen Clancy @ G-328 H.S.B.
May 16 @ 9:30 am – 10:30 am
Colleen Clancy UC Davis   host: Sharona Gordon
PBIO seminar series: Rachel Martin @ G-328 H.S.B.
May 23 @ 9:30 am – 10:30 am
What can we learn about protein solubility and aggregation from a cold fish?
Rachel Martin
Professor Departments of Chemistry and Molecular Biology & Biochemistry UC Irvine
host: Sharona Gordon
seminar abstract: The βγ-crystallin fold that is ubiquitous in the structural proteins of the vertebrate eye lens is an ancient structural motif found in diverse organisms from all three domains of life. In organisms without eyes, e.g. archaea, bacteria, tunicates, and sponges, βγ-crystallins serve as calcium-binding proteins.  In vertebrates, they are primarily found in the eye lens, where they play an important role in controlling the refractive index gradient of this specialized tissue.  The ubiquitous βγ-crystallins of the vertebrate lens are believed to have descended from an ancestral single-domain Ca2+-binding crystallin by a process that included gene duplication resulting in two copies of the double Greek key domain per chain, as well as selection for high refractive index. Because the lens has negligible protein turnover, the crystallins must remain stable and soluble for the lifetime of the organism despite their extremely high concentrations. In particular, we are interested in the resistance to phase separation of the cold-adapted crystallins of the Antarctic toothfish, Dissostichus mawsoni. The eye lens of D. mawsoni is evolutionarily adapted to function in the permanently sub-freezing waters of the Southern Ocean.  This is in contrast to temperate and tropical fishes, and endothermic mammals, the lenses of which undergo liquid-liquid phase separation at low temperatures.  Mammalian lenses phase separate at temperatures between 10 °C and 20 °C – well above the Antarctic’s sub-zero marine environment.  The ability of the toothfish lens to maintain transparency in this frigid environment is particularly remarkable given that fish lenses have a high concentration of constituent proteins ≥1000 mg * mL-1). Recent work in my group focuses on testing the hypothesis that γ-crystallin isoform heterogeneity coupled with cold selective evolutionary pressures contribute to the clarity of the toothfish lens.  We have measured the thermal stabilities and phase diagrams of seven key γ-crystallin lens proteins, and we are able to control the onset of liquid-liquid phase separation by introducing a small number of surface mutations. The implications of our findings with respect to the roles of frustration, ionic interactions, and protein flexibility liquid-liquid phase separation will be discussed.  
2019 Crill Lecture – Leslie B. Vosshall @ HSB T-625
Jun 6 @ 4:00 pm – 5:00 pm host: Stan Froehner