Calendar Name: seminars
Scheduled for: Tuesday, April 17 2012, 14:00 - 15:30
Event text: Prof Jaideep Mathur
Laboratory of Plant Development and Interactions
Department of Molecular and Cellular Biology
University of Guelph
Guelph
Ontario
CANADA
Details: �Organelle Extensions: Uncovering new facets of
subcellular behaviour for maintaining homeostasis in
plants�
ABSTRACT
Despite their inability to move away from stressful
conditions, plants, in comparison to animals, have much
longer life spans. How do plants manage stress while
remaining 'rooted' to a spot? Perhaps, plant cells are
able to respond to environmental stimuli rapidly and
minimize subcellular stress levels before they become
intolerable. Perhaps they do not need to move away! This
fundamental thinking forms the basis for research in my
lab. Using a judicious combination of molecular-genetic
techniques including a wide range of targeted
fluorescent protein probes, normal and mutant transgenic
plants we have started uncovering the rapid sub-cellular
response machinery in plants. We find that instead of
dividing, many organelles extend their surfaces
transiently by creating thin protrusions that can extend
for considerable distances within the cell. This
�primary� membrane-aided response prevents the build up
of toxic by-products within the cell. Alternatively,
organelle extensions are used for metabolite dispersal
and exchange, as well as for �squeezing� past other
organelles in narrow vacuole-dominated intracellular
spaces. Notably, persistent stress acting on membranes
does trigger molecular cascades that over a longer time
scale result in division of organelles. Live-imaging of
organelle extensions and their dynamic interactions
challenges our view of the static plant cell built up
using snapshots from fixed tissues and paves the way for
a better understanding of plants and their rapid
subcellular responses.
