Plant Immunity

An End to Plant Defenses

Science Signaling  21 Jun 2011:
Vol. 4, Issue 178, pp. ec172
DOI: 10.1126/scisignal.4178ec172

When defending against bacterial pathogens, plants make use of an innate immunity system that detects molecular signatures of bacteria. The plant defense response depends on receptors including the pattern recognition receptor FLAGELLIN-SENSING 2 (FLS2) and initiates a cascade of responses that deflect bacterial attack. However, always being on the defensive does not work out well for plants: Once activated, defense systems need to be turned off. Studying Arabidopsis, Lu et al. (see the Perspective by O’Neill) have now analyzed this shutdown protocol. Once FLS2 is activated by binding to bacterial flagellin and to co-receptors, it becomes the target for a ubiquitination cascade that results in its degradation.

D. Lu, W. Lin, X. Gao, S. Wu, C. Cheng, J. Avila, A. Heese, T. P. Devarenne, P. He, L. Shan, Direct ubiquitination of pattern recognition receptor FLS2 attenuates plant innate immunity. Science 332, 1439–1442 (2011). [Abstract] [Full Text]

L. A. J. O’Neill, Innate immunity in plants goes to the PUB. Science 332, 1386–1387 (2011). [Abstract] [Full Text]