Edinburgh, Scotland, United Kingdom - TAIR

Cellular dynamics in plant immunity L17
Friday 11:30 - 12:00
Cell Biology
Plant defence in response to pathogen infection is tightly associated with
reprogramming of vesicle trafficking pathways. These include exocytic/secretory
routes for focal accumulation at pathogen penetration sites, and endocytic
pathways. To better understand the contribution of endocytic trafficking in plant
immunity we combine molecular and genetic approaches with cell biology. We
monitor, for example, defence reactions of mutants in known endocytosis
components upon pathogen infection. Previously, the FLS2 receptor responsible
for perception of bacterial flagellin (flg22) was demonstrated to undergo induced
internalization. In an attempt to identify molecular components of FLS2 endocytosis
we isolated FLS2 interacting proteins. FIP1 localizes to the plasma
membrane and like FLS2 accumulates into endosomes upon flg22 elicitation.
The function of FIP1 function in plant development and immunity will be
discussed. To additionally elucidate the role of endocytic vesicle traffic during
plant defence we established a genetic screen for endocytosis mutants and
applied high throughput quantitative confocal laser microscopy (QCLM), which
will be described. We identified 12 fel mutants (fel = FYVE endosome levels)
with elevated or reduced vesicle numbers. Interestingly, fel4 not only displayed
increased vesicle numbers but also enlarged vesicles, while fel5 exhibits tissuespecific
differences in endosomal numbers. Characterization of fel mutant
phenotypes will be presented.
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Silke Robatzek
Nicolas Frei dit Frey
Yi-Ju Lu
Susanne Salomon
Thomas Spallek
Max-Planck-Institute for
Plant Breeding Research
Carl-von-Linne-Weg
1050829 Cologne
Germany