Present address: Unibioscreen, 40 Ave. J. Wybran, 1070 Brussels, Belgium.
Arabidopsis thaliana subcellular responses to compatible Erysiphe cichoracearum infections
Article first published online: 7 OCT 2005
The Plant Journal
Volume 44, Issue 3, pages 516–529, November 2005
How to Cite
Koh, S., André, A., Edwards, H., Ehrhardt, D. and Somerville, S. (2005), Arabidopsis thaliana subcellular responses to compatible Erysiphe cichoracearum infections. The Plant Journal, 44: 516–529. doi: 10.1111/j.1365-313X.2005.02545.x
- Issue published online: 7 OCT 2005
- Article first published online: 7 OCT 2005
- Received 24 May 2005; revised 3 August 2005; accepted 8 August 2005.
- green fluorescent protein;
- haustorial complex;
- laser scanning confocal microscopy;
- plant–pathogen interactions;
- powdery mildew
Subcellular events of Erysiphe cichoracearum infections of epidermal cells were visualized in living tissues of Arabidopsis plants carrying various green fluorescent protein (GFP)-tagged organelles via laser scanning confocal microscopy. Early in the infection sequence, cytoplasm and organelles moved towards penetration sites and accumulated near penetration pegs. Peroxisomes appeared to accumulate preferentially relative to the cytoplasm at penetration sites. Another early event, which preceded haustorium formation, was the aggregation of some GFP-tagged plasma membrane marker proteins into rings around penetration sites, which extended across cell-wall boundaries into neighboring cells. This feature localized to sites where papillae were deposited. The extrahaustorial membrane (EHM) encases the fungal feeding structure, the haustorium, separating it from the host cytoplasm. Eight plasma membrane markers were excluded from the EHM and remained in a collar-like formation around the haustorial neck. These observations support the suggestions that the EHM is a unique, specialized membrane and is different from the plasma membrane. Our results suggested two possibilities for the origin of the EHM: invagination of the plasma membrane coupled with membrane differentiation; or de novo synthesis of the EHM by targeted vesicle trafficking.