9:15 am–12:00 noon
Session I. Recent Concepts in Membrane Heterogeneity
Chair: Michael Edidin, Johns Hopkins University

Issues:

1. How much does molecular and vesicular traffic to and from the surface contribute to the formation and dispersion of lipid domains? Are the domains formed in model membranes any guide to domain formation and dispersion in native membranes?

2. How effectively can we use model membrane data to infer organization of cell membranes?

3. Are we missing/ignorant of proteins that organize membrane lipids? The caveolin-1 knockout mouse can be interpreted as showing redundancy of caveolin function?

4.  Who organizes whom in signaling? Do ligated receptors partition into preexisting rafts or do they organize non-annular lipids into a raft?

Unsolved Questions about caveolae and Lipid Rafts
Dick Anderson, UTHSC, Dallas

Respondent (Role of respondent is to discuss/comment on the speaker's work)

Tobias Baumgart

Regulation of the Spatial Organization of Signal-transducing Receptors within the Plasma Membrane of B Lymphocytes 
Sue Pierce, NIH

Respondent (Role of respondent is to discuss/comment on the speaker's work)

Francisco Barrantes

Nanoclusters
Satyajit Mayor, National Center for Biological Sciences, Bangalore

Respondent (Role of respondent is to discuss/comment on the speaker's work)

Samuel Hess

Single Molecule Imaging of Raft Dynamics and Raft-based Signal Transduction in Living Cells
Aki Kusumi, Nagoya University

Respondent (Role of respondent is to discuss/comment on the speaker's work)

Christoph Naumann

Membrane Domains and Lipid Traffic
Fred Maxfield, Cornell Medical College

Break

General Discussion

12:00 Noon

7:00 pm–10:00 pm
Session II. How Can the Lessons from Model Membranes be Applied to Cell Membranes?
Chair: John Silvius, McGill University

Part I.

Focus Questions for Presenters: What are the Origins, Properties and Thermodynamics of Liquid-ordered Domains?

Chemical Activity of Cholesterol in Membranes
Harden McConnell, Stanford University

How Can the Lessons from Model Membranes be Applied to Cell Membranes
Gerry Feigenson, Cornell University

Kinetics of the Association of Amphiphiles with Lipid Bilayers as a Probe of Membrane Physical State
Winchil Vaz, University of Coimbra, Portugal

Open Discussion

Using Fluorescence Microscopy and NMR to Identify Immiscible Liquid Phases in Vesicles
Sarah Keller, University of Washington

Understanding the Role of Lipid Structure in Raft Formation by use of Novel Fluorescence Approaches for Detecting Nanoscale Lipid Domains
Erwin London, SUNY, Stony Brook

Respondent (Role of respondent is to discuss/comment on the speaker's work)

Ivan Polozov

Open Discussion

Break

Role of Bilayer Structural/Elastic Properties in THE Sorting of Transbilayer Peptides Between Detergent Soluble Bilayers and Detergent Resistant Rafts
Tom McIntosh, Duke University

Saturday October 30, 2004
9 am–12:00 noon
Session III. Microscopy and Novel Biological Functions of Membrane Domains
Chair: Barbara Baird, Cornell University

Issues:

Overview: Microscopy with selective probes has been a central approach to investigating organization and dynamics of plasma membranes. However, images or measurements can be limited by sample or probe preparations, and any single type of measurement provides limited information. For example, diffraction limits optical microscopy in  examining molecular interactions such as they occur to create function in membrane microdomains. Targeted biological reagents (e.g., viral proteins, toxins) or engineered environments (e.g. nanofabrication) provide some advantages. In describing standard and emerging approaches, the speakers will frame and address specific questions about microdomains in living cells and focus on the following issues:

1. What  fundamental new information has a particular approach provided so far about membrane microdomains  on living cells

2. What are the unique capabilities and what are the major limitations of this approach?What should be our highest expectations for a particular approach - in strategic combination with other selected approaches -- to provide a detailed understanding of membrane microdomains on living cells?

3. Each respondent will address the same issues with respect to specific points made by the preceding speakers

Introduction

Barbara Baird, Cornell University

 

FRAP Approaches to Studying Lipid Rafts
Anne Kenworthy, Vanderbilt University

Strengths and Weaknesses of Single-Molecule Tracking
Marija Vrljic, Stanford University

Strengths and Limitations of FCS as Applied to Microdomains
Petra Schwille, University of Dresden of Technology

Respondents (Role of respondent is to discuss/comment on the speaker's work)

Antoine Triller

Erin Sheets

Tione Buranda

Discussion 1

Break

Probing Membrane Microdomains with Atomic Force and Near-field Scanning Optical Microscopy
Linda Johnston, National Research Council, Ottawa

Respondent (Role of respondent is to discuss/comment on the speaker's work)

Marjolein Koopman

What Undesired Foreigners Tell us about Lipid Rafts and Membrane Domains
Gisou Van der Goot, University of Geneva

Strategies for Studying the Size, Structure, and Function of Rafts in Cells
Josh Zimmerberg, NIH

 

Discussion 2

3:00 pm–5:00 pm
Poster Session II  
Posters 52-103 will be presented.

7:00 pm–10:00 pm
Session IV. Inner Leaflet and Membrane Associated Cytoskeleton
Chair: Kai Simons, Max Planck Institute of Molecular Cell Biology and Genetics

Issues:

1. How and when does the outer leaflet couple with the inner leaflet in raft microdomains in cell membranes?

2. What do we know about the binding of proteins to the inner leaflet of cell membranes and does this information give us insight into membrane domain organization?

3. What do we know about the organization of the underlying actin cytoskeleton with respect to lateral mobility of bilayer constituents?

Too Many Proteins at the Membrane Looking for Lipids
Mike Sheetz, Columbia University

How Clusters of Basic/Hydrophobic Residues on Proteins Interact with Lipids in Membranes
Stuart McLaughlin, SUNY, Stony Brook

Plasma Membrane/Endoplasmic Reticulum Junctions and Sub-plasmalemmal Spaces
Mordecai Blaustein, University of Maryland

Sunday, October 31, 2004
7:30 am–10:30 am
Session V. Emerging Physical and Computational Techniques
Chairs: Michael Saxton, University of California, Davis
            Nancy Thompson, University of North Carolina

Issues:

1. What are the advantages and disadvantages of the different emerging experimental methods (FCS, FLIM, X-ray, Neutron, etc.)?  How do these techniques compare in terms of

   (a) applicability to live/fixed cells and/or model membranes,

   (b) possible artifacts coming from sample preparation,

   (c) spatial resolution

   (d) temporal resolution

   (e) sensitivity? 

    

• How can measurements be designed so that the results of these different methods are most easily compared in a fruitful fashion? 

• How do these methods compare in their abilities to definitely address key raft questions raised during the previous talks of the conference?

 

2. How can we better connect computational studies with experiment?

   "Modeling a raft" is nice but the work would be far more useful if it focused on specific existing hypotheses of raft structure: 

   • Lipid-cholesterol complexes

   • Sheltering of cholesterol from water

   • Selectivity for certain membrane proteins

   • The Lo-Ld interface and localization of certain species there

    

   More generally, how can we get closer linkage between simulation and experiment in order to generate and test hypotheses?

    

   Introduction

   Michael Saxton, University of California, Davis
   Nancy Thompson, University of North Carolina

    

   Fluorescence Correlation Spectroscopy Techniques
   Enrico Gratton, UIUC

• Specific questions for speaker, talk #1

The use of Single Domain Llama Antibodies in FLIM
Paul van Bergen en Henegouwen, University of Utrecht

• Specific questions for speaker, talk #2

Spatio-Temporal Imaging of Signal Transduction Processes in Single Cells
Banafshe Larijani, London Research Institute

• Specific questions for speaker, talk #3

Could Diffuse Scattering of X-Rays and/or Neutrons Provide Structural Information about Rafts?
John Nagle, CMU

• Specific questions for speaker, talk #4

Modeling Mixed Lipid Bilayers: Atomic and Ginzburg-Landau Simulations
Larry Scott, Illinois Institute of Technology

• Specific questions for speaker, talk #5

A Plead for ζ
Ole Mouritsen, Odense, Denmark

• Specific questions for speaker, talk #6

Break

 

Respondents (Role of respondent is to discuss/comment on the speaker's work)

Paul Wiseman

Roland Winte

Martin Zuckermann

Scott Feller

General Discussion

Meeting ends