| Title: | Signatures of plant defense response specificity mediated by herbivore-associated molecular patterns in legumes |
| Author(s): | Steinbrenner AD; Saldivar E; Hodges N; Guayazan-Palacios N; Chaparro AF; Schmelz EA; |
| Address: | "Department of Biology, University of Washington, Seattle, WA, USA. Washington Research Foundation, Seattle, WA, USA. Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA. Department of Biology, Stanford University, Stanford, CA, 94305, USA. Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA" |
| ISSN/ISBN: | 1365-313X (Electronic) 0960-7412 (Linking) |
| Abstract: | "Chewing herbivores activate plant defense responses through a combination of mechanical wounding and elicitation by herbivore-associated molecular patterns (HAMPs). HAMPs are wound response amplifiers; however, specific defense outputs may also exist that strictly require HAMP-mediated defense signaling. To investigate HAMP-mediated signaling and defense responses, we characterized cowpea (Vigna unguiculata) transcriptome changes following elicitation by inceptin, a peptide HAMP common in Lepidoptera larvae oral secretions. Following inceptin treatment, we observed large-scale reprogramming of the transcriptome consistent with three different response categories: (i) amplification of mechanical wound responses, (ii) temporal extension through accelerated or prolonged responses, and (iii) examples of inceptin-specific elicitation and suppression. At both early and late timepoints, namely 1 and 6 h, large sets of transcripts specifically accumulated following inceptin elicitation. Further early inceptin-regulated transcripts were classified as reversing changes induced by wounding alone. Within key signaling- and defense-related gene families, inceptin-elicited responses included target subsets of wound-induced transcripts. Transcripts displaying the largest inceptin-elicited fold changes included transcripts encoding terpene synthases (TPSs) and peroxidases (POXs) that correspond with induced volatile production and increased POX activity in cowpea. Characterization of inceptin-elicited cowpea defenses via heterologous expression in Nicotiana benthamiana demonstrated that specific cowpea TPSs and POXs were able to confer terpene emission and the reduced growth of beet armyworm (Spodoptera exigua) herbivores, respectively. Collectively, our present findings in cowpea support a model where HAMP elicitation both amplifies concurrent wound responses and specifically contributes to the activation of selective outputs associated with direct and indirect antiherbivore defenses" |
| Keywords: | "Animals *Fabaceae/genetics Gene Expression Regulation, Plant Herbivory/physiology Plants Spodoptera Terpenes/metabolism *Vigna/genetics Hamp Inr Vigna unguiculata cowpea inceptin peroxidase terpene;" |
| Notes: | "MedlineSteinbrenner, Adam D Saldivar, Evan Hodges, Nile Guayazan-Palacios, Natalia Chaparro, Antonio F Schmelz, Eric A eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. England 2022/03/23 Plant J. 2022 Jun; 110(5):1255-1270. doi: 10.1111/tpj.15732. Epub 2022 Apr 8" |
