Plants strike back: Kiwellin proteins as a modular toolbox for plant defense mechanisms

ABSTRACT

Plants have to cope with numerous stresses in nature to avoid damage or cell death. We recently reported a class of plant defense proteins termed kiwellins that were initially found in kiwifruit and shown to be causative to human food allergies. While kiwifruits among other domestic fruits always contain high amounts of kiwellin protein, available transcriptome data indicate an up-regulation of kiwellin genes upon pathogen contact in various other plants. In the case of an interaction between maize plant and the smut fungus Ustilago maydis, we could identify one kiwellin (termed: ZmKWL1) highly up-regulated in response to pathogen attack. During infection of the maize plant, U. maydis secretes numerous effector proteins that modulate the host. Among 20 predicted kiwellins, ZmKWL1 specifically inhibits the metabolic activity of the secreted fungal chorismate mutase 1 (Cmu1). We expand the current knowledge on kiwellins and describe a novel class of versatile plant defense proteins.

KEYWORDS:

• Pathogen-related proteins
• Ustilago maydis
• chorismate
• kiwellin

Acknowledgments

G.B. acknowledges support by the Deutsche Forschungsgemeinschaft (DFG) through the DFG-core facility for interactions, dynamics and macromolecular assembly structure and the Collaborative Research Council SFB987. F.A. was supported by the Peter and Traudl Engelhorn foundation.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the DFG [SFB987].