Conference Program
 
PHOTOSENSORY RECEPTORS & SIGNAL TRANSDUCTION

April 30 - May 5, 2000
Il Ciocco Hotel and Resort
Lucca (Barga), Italy

Chairs:
John L. Spudich & Winslow Briggs

Light is one of the most important signals providing critical information to biological systems. In addition to giving us visual input, light controls movement, growth, differentiation and development, circadian timing, and a host of gene-expression responses in diverse organisms from primitive unicellular microbes through higher plants and animals. The conference will focus on current research on photosensory receptors, covering their mechanisms of photoactivation and downstream elements of their signal transduction pathways. This area of research is a fast-moving one, and progress is being made on several long-standing fundamental questions: By what mechanisms is photon energy captured and stored in photoreceptor proteins? How is light color discriminated? How do photoactivated receptor proteins communicate their signals to the cell? Investigators who study photosensory receptors in very different systems (e.g. plants, animals, eukaryotic microbes, and prokaryotes) are confronting many of the same research challenges. However in recent years there has not been a dedicated meeting bringing together this group. Given the rapid advances currently being made, a Photosensory Receptors conference bringing together scientists studying photoreceptors and their immediately downstream signal transduction components is particularly appropriate. It will provide a very much-needed opportunity to exchange information and ideas and to become aware of some of the diverse tools available.

Several new classes of photosensory receptors have been discovered in the last few years. These include the flavoprotein cryptochromes in both plants and animals; the photoreceptor for phototropism, phototropin, in plants; retinal proteins homologous to archaeal rhodopsins in eukaryotic microbes, phytochromes in prokaryotes homologous to those in higher plants, and photoactive yellow proteins (PYPs) in photosynthetic bacteria. There are already genome projects that are clarifying their distribution in nature. Their mechanisms of activation and signal transduction are being unraveled at a rapid pace and we expect the conference will stimulate exciting discussion of emerging insights, general principles, and the most engaging mysteries on the cutting edge of photosensory signal transduction.

Sunday Evening, April 30, 7:30-9:45 pm

7:30 pm Brief Welcome by Chairs
SESSION I. Phototransduction: Insights from 3D Atomic Structure & Dynamics
7:40 pm Discussion Leader: Sriram Subramaniam (MRC Cambridge, UK)
7:45 pm Elizabeth Getzoff (Scripps)
Time-resolved crystallography of photoactive yellow protein (PYP)
8:15 pm Keith Moffat (U. Chicago)
Nanosecond time-resolved crystallographic studies of blue light photoreceptors
8:45 pm Janos Lanyi (UC Irvine)
Structural basis of the directional proton transfers in the bacteriorhodopsin transport cycle
9:15 pm Sriram Subramaniam (MRC Cambridge, UK)
Structural basis of proton transport by bacteriorhodopsin

Monday Morning, May 1, 9:00-12:30 am

SESSION II. Archaeal Rhodopsins
9:00 am Discussion Leader: John Spudich (UT Houston)
9:05 am Lars-Oliver Essen (Max-Planck-Inst., Martinsried, Germany)
The 1.8 Å X-ray structure of halorhodopsin: Mechanistical equivalence of proton and chloride transport?
9:35 am Kenneth Rothschild (Boston Univ)
Conformational changes in sensory rhodopsins detected by molecular spectroscopy
10:05 am BREAK & PHOTOGRAPH
10:45 am Roberto Bogomolni (UC Santa Cruz)
Rotational diffusion reveals photoreceptor/ transducer stoichiometry and structural perturbations in sensory rhodopsin I
11:10 am Silvia Braslavsky (Max-Planck-Inst., Muehlheim, Germany)
Protein movements in photosensors as determined by photothermal methods
11:35 am Martin Engelhard (Max-Planck-Inst., Dortmund, Germany)
Interaction of pharaonis sensory rhodopsin II with its transducer
12:00 noon Minitalk: Naoki Kamo (Sapporo University, Japan)
Photochemical reaction of pharaonis phoborhodopsin (sensory rhodopsin II)
12:15 pm Minitalk: Donatella Petracchi (CNR Biophysics, Pisa)
Competition-integration of blue and orange stimuli in Halobacterium salinarum cannot occur solely in the photoreceptor

Monday Evening, May 1, 5:30-7:30 pm

SESSION III. Photosensory Receptors in Eukaryotic Microbes
5:30 pm Discussion Leader: Francesco Lenci (CNR, Pisa)
5:35 pm Giuseppe Macino (CNR, Rome)
Photosensory and transcriptional coupled system in Neurospora crassa
6:05 pm Katherine Borkovich (UT Houston)
NOP-1 represents a new class of opsins in fungi
6:35 pm Peter Hegemann (University of Regensburg, Germany)
Algal rhodopsins operate as light-regulated ion channels that mediate fast behavioral responses in lower plants
7:05 pm Minitalk: Oleg Sineshchekov (Moscow Univ., Russia)
Chlamydomonas phototaxis reception
7:20 pm Minitalk: Paolo Gualtieri (CNR Biophysics, Pisa)
Rhodopsin in the photoreceptor of Euglena gracilis

Tuesday Morning, May 2, 9:00-12:30 am

SESSION IV. Mammalian Visual Pigments
9:00 am Discussion Leader: Klaus Peter Hoffman (Humboldt Univ., Berlin)
9:05 am Klaus Peter Hoffman (Humboldt Univ., Berlin)
Binding reactions of light-activated rhodopsin with multiple signal transduction proteins
9:35 am Gebhard Schertler (MRC Cambridge, UK)
Structure of bovine rhodopsin
10:05 am BREAK
10:30 am Wayne Hubbell (Jules Stein, UCLA)
A new spin on rhodopsin activation
11:00 am Kevin Ridge (CARB, Rockville MD)
Effective mimicry of rhodopsin signaling functions by an engineered cytoplasmic domain
11:30 am Tom Sakmar (Rockefeller University, New York)
Retinal-protein interactions in visual pigments
12:00 noon Fritz Siebert (Albert-Ludwigs-University, Germany)
The molecular mechanism of transducin activation inhibition in 9-desmethyl rhodopsin: a UV-vis and FTIR study

Tuesday Evening, May 2, 5:30-7:30 pm

SESSION V. Cryptochromes
5:30 pm Discussion Leader: Giuseppe Macino (CNR, Rome)
5:35 pm Anthony R. Cashmore (University of Pennsylvania)
The cryptochrome families of blue light receptors
6:05 pm Alfred Batschauer (Philipps Univ, Marburg, Germany) The Arabidopsis blue light receptor cryptochrome 2
6:35 pm Paul Devlin (Scripps, La Jolla)
Circadian photoreception in Arabidopsis
7:05 pm Christian Fankhauser (University of Geneva)
Genetic interactions between phytochromes and cryptochromes during Arabidopsis development

Wednesday Morning, May 3, 9:00-12:00 noon

SESSION VI. Phototropin
9:00 am Discussion Leader: Peter H. Quail (UC Berkeley)
9:05 am Winslow R. Briggs (Carnegie Inst., Stanford)
Phototropin, the photoreceptor for phototropism
9:35 am John M. Christie (Carnegie Inst., Stanford)
Characterization of FMN binding to phototropin
10:05 am BREAK
10:30 am Michael Salomon (Univ. Munich, Germany)
On the molecular nature of autophosphorylation, flavin-binding and photoactivation of the plant blue light photoreceptor phototropin (NPH1)
11:00 am Masamitsu Wada (Tokyo Metropolitan University)
Phototropins and related photoreceptors in ferns and mosses
11:30 am Minitalk: Tatsuya Sakai (University of Kyoto)
Signaling pathways to induce the phototropic response in Arabidopsis
11:45 am Minitalk: Rainer Hertel (University of Freiburg, Germany
Flavin-binding proteins from yeast, Phycomyces and Euglena

Wednesday Evening, May 3, 5:30-7:30

SESSION VII. Phytochromes in Higher Plants
5:30 pm Discussion Leader: Pill-Soon Song (Univ. Nebraska & Kumho Life & Env. Science Lab, Korea)
5:35 pm Pill-Soon Song (Univ. Nebraska & Kumho Life & Env. Science Lab, Korea)
Structure and function of phytochrome A
6:05 pm M. Furuya (Hitachi Advanced Research Laboratories, Japan)
Phytochromes A and B: Multiple photoperception and down-stream responses
6:35 pm Peter H. Quail (UC Berkeley)
Downstream signaling elements in phytochrome-activated signal transduction pathways
7:05 pm Seth J. Davis (University of Wisconsin)
Bacteriophytochromes: phytochrome-like photoreceptors from nonphotosynthetic eubacteria

Thursday Morning, May 4, 9:00-12:30 pm

9:00 am Business meeting (to discuss future meeting plans, etc.)
SESSION VIII. Phytochromes in Lower Plants and Cyanobacteria
9:30 am Discussion Leader: Winslow R. Briggs (Carnegie Institute, Stanford)
9:35 am Jonathan Hughes (Free Univ. of Berlin, Germany)
Characterisation of phytochrome from Synechocystis
10:05 am BREAK
10:35 am David Kehoe (Indiana Univ.)
Light regulation of gene expression in cyanobacteria
11:05 am Wolfgang Gaertner (Max-Planck-Inst., Martinsried, Germany)
Cyanochromes
11:35 am Tilman Lamparter (Free Univ. of Berlin, Germany)
Phytochrome in moss protonemata
12:05 am Minitalks: to be arranged

Thursday Evening, May 4, 5:30-7:30 pm

SESSION IX. Photoactive Yellow Proteins (PYPs) & PAS Domains
5:30 pm Discussion Leader: Elizabeth Getzoff (Scripps)
5:35 pm Klaas Hellingwerf (Univ. Amsterdam)
Signal generation and signal transduction in the family of Photoactive Yellow Proteins, the Xanthopsins
6:05 pm Carl Bauer (Univ. Indiana, Bloomington)
Photosensory perception by purple photosynthetic bacteria
6:35 pm Gordon Tollin (Univ. Arizona)
Photoactive Yellow Protein: What have we learned from transient kinetic spectroscopy?
7:05 pm Concluding Remarks
Last Updated: May 4, 2006