Actin filament assembly in plants is a dynamic process, requiring the activity of more than 75 actin‐binding proteins. Central to the regulation of filament assembly and stability is the activity of a conserved family of actin‐depolymerizing factors (
- Award ID(s):
- 1901566
- NSF-PAR ID:
- 10206425
- Date Published:
- Journal Name:
- Phytopathology®
- ISSN:
- 0031-949X
- Page Range / eLocation ID:
- PHYTO-05-20-017
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary ADF s), whose primarily function is to regulate the severing and depolymerization of actin filaments. In recent years, the activity ofADF proteins has been linked to a variety of cellular processes, including those associated with response to stress. Herein, a wheat gene,ADF Ta was identified and characterized.ADF 4,Ta encodes a 139‐amino‐acid protein containing five F‐actin‐binding sites and two G‐actin‐binding sites, and interacts with wheat (ADF 4Triticum aestivum ) Actin1 (TaACT 1),in planta . Following treatment of wheat, separately, with jasmonic acid, abscisic acid or with the avirulent race,CYR 23, of the stripe rust pathogenPuccinia striiformis f. sp.tritici , we observed a rapid induction in accumulation ofTa ADF 4mRNA . Interestingly, accumulation ofTa ADF 4mRNA was diminished in response to inoculation with a virulent race,CYR 31. Silencing ofTa resulted in enhanced susceptibility toADF 4CYR 23, demonstrating a role forTa in defense signaling. Using a pharmacological‐based approach, coupled with an analysis of host response to pathogen infection, we observed that treatment of plants with the actin‐modifying agent latrunculin B enhanced resistance toADF 4CYR 23, including increased production of reactive oxygen species and enhancement of localized hypersensitive cell death. Taken together, these data support the hypothesis thatTa ADF 4 positively modulates plant immunity in wheat via the modulation of actin cytoskeletal organization. -
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