KeyNote Speaker - 2012

2012 Keynote Speaker

Paul Kulesa, PhD

Associate Professor and Director of Imaging/KulesaLab
Stowers Institute for Medical Research

'Visualizing dynamic multiscale events in the embryo'

 Wednesday, July 18th, 7PM, Martin Theatre, McGill University McIntyre Building

Followed by a reception (Free but registration required).

If you are not participating in the MLMC, please register for the keynote here.

The frontier of biology and medicine is being defined by our ability to decipher the mechanisms that underlie basic phenomena.  These phenomena may include well coordinated, complex cell migration and cell division events as an embryo sculpts a population of cells into distinct structures.  Although significant advances in imaging technology now allow visualization of single cell behaviors in the living embryo, it has become clear that collection of accurate multiscale data in the same in vivo model system will greatly impact our ability to study basic phenomena. 

Here, I will discuss our recent advances to develop an in vivo biological imaging platform that permits the collection of multiscale data during complex events in the living chick embryo.   To follow collective cell migration events in more detail, I will describe our design of multispectral imaging strategies that more accurately trace complex cell trajectories that intersect, using a cell’s spectral profile for identification in addition to shape and brightness. To link cell migration and cell division events, I will discuss our recently developed fluorescent reporter system that allows a dynamic readout of cell cycle progression.  Lastly, I will show how collection of cell dynamics data can be combined with laser capture microdissection to provide a readout of gene expression data.

By combining these distinct strategies, our goal is to obtain multiscale data of cell position, cell-to-cell contact, cell cycle, and gene expression profile within the same embryo model system.  I will discuss these concepts within the framework of our studies of cancer metastasis. 

 

 About the Speaker

Dr. Paul Kulesa was a Sloan Foundation and Burroughs Wellcome Fund postdoctoral fellow at the California Institute of Technology in the laboratory of Prof. Scott E. Fraser. He received a bachelor’s degree in aerospace engineering from the University of Notre Dame and a Ph.D. in applied mathematics from the University of Washington, under Prof. J.D. Murray. Dr. Kulesa joined the Stowers Institute for Medical Research in 2003 and is currently an Associate Professor and Director of Imaging. His research goals are to better understand the mechanisms that regulate cell migration in the developing vertebrate embryo and to determine the relevance of these signaling pathways in the control of tumor cell invasion and reprogramming of the metastatic phenotype, using the neural crest model system. His interdisciplinary approach includes manipulation of cells and tissue within the avian embryo, visualization of individual fluorescently labeled cell behaviors and computational modeling to integrate theory and experiment.

 

 

Previous KeyNote Speaker - Sergio Grinstein, PhD 2010

Senior Scientist, Cell Biology,The Hospital for Sick Children Research Institute Professor Biochemistry, University of Toronto

Pitblado Chair in Cell Biology, The Hospital for Sick Children

 Imaging phagocytosis: receptors, phospholipids and the cytoskeleton

McGill University, McIntyre Medical Building, Charles F. Martin Amphitheatre, 6th Floor, 3655 Promenade Sir William Osler

Open to all (you need to be involved in the Montreal Light Microscopy Course to attend). However,  registration is required as we need an accuate head count for the reception afterwards. Participants in the morning course must register for this event separately while whole-day participants do not.

Abstract

Engulfment and elimination of microorganisms by macrophages and neutrophils is an essential component of the innate immune response. This process, known as phagocytosis, involves reconfiguration of the membrane and extensive remodeling of the actin cytoskeleton. These responses are rapid, transient and highly localized, complicating their analysis by conventional biochemical means. We studied the signals involved in phagosome generation and maturation by digital imaging of live cells to analyze spatio-temporal features of signal transduction and membrane remodeling during phagosome formation and maturation. Receptors were tracked at the single-molecule level by labeling with fluorescently-labeled Fab fragments of specific antibodies, while components of the signal transduction cascade and of the cytoskeleton were visualized using chimeras tagged with green or red fluorescent proteins. This dynamic analysis has provided evidence of a complex, highly localized sequence of reactions that are carefully choreographed to enable the phagocyte to extend pseudopods to encircle the target particle and internalize it into a vacuole. This newly formed intracellular vacuole, known as the phagosome, subsequently undergoes a series of fusion and fission reactions with endomembrane compartments, a process called maturation that confers microbicidal and digestive properties to the maturing compartment. The talk will emphasize the power of imaging to elucidate processes that, like phagocytosis, are exquisitely localized and occur rapidly, transiently and asynchronously in a population of cells.

Dr. Sergio Grinstein is a senior scientist in the The Hospital for Sick Children Research Institute, holder of the Pitblado Chair in Cell Biology at The Hospital for Sick Children (SickKids), and a professor of Biochemistry at the University of Toronto. He is internationally recognized for his research in two areas: the control of intracellular pH and the elucidation of mechanisms underlying the microbicidal response of macrophages and neutrophils.

Dr. Grinstein completed his PhD in 1976 at the Centro de Investigacion y Estudios Avanzados in Mexico City. He then spent two years as a postdoctoral fellow in Cell Biology at Sick Kids, followed by a year in the Department of Biochemistry at the Federal Institute of Technology in Zurich. He has been an International Scholar of the Howard Hughes Medical Institute and recipient of the Canadian Institutes of Health Research Distinguished Scientist Award, and is a Fellow of the Royal Society of Canada.

Research Activities

Two major areas are under study in my laboratory. The first one investigates the molecular mechanisms utilized by white blood cells to eliminate infectious organisms. More specifically, we are studying the processes whereby macrophages and neutrophils migrate to sites of infection, ingest microbes and destroy them, as well as the strategies used by certain microorganisms to outsmart the immune system and avoid killing.

The second area deals with the regulation of ion transport and pH of intracellular compartments. We have devised means of measuring the pH and ionic composition of individual organelles within intact live cells and are currently investigating the identity and properties of the molecules responsible for transport of ions and for intracellular acid/base regulation.