Title: | Activation of the Phenylpropanoid pathway in Nicotiana tabacum improves the performance of the whitefly Bemisia tabaci via reduced jasmonate signaling |
Author(s): | Alon M; Malka O; Eakteiman G; Elbaz M; Moyal Ben Zvi M; Vainstein A; Morin S; |
Address: | "Department of Entomology, the Hebrew University of Jerusalem, Rehovot, Israel" |
DOI: | 10.1371/journal.pone.0076619 |
ISSN/ISBN: | 1932-6203 (Electronic) 1932-6203 (Linking) |
Abstract: | "BACKGROUND: Phloem-feeding insects can manipulate plant-induced resistance and are able to suppress effective jasmonic acid/ethylene (JA/ET) defenses by the induction of inefficient salicylic acid (SA) based responses. As a result, activation of the phenylpropanoid biosynthesis pathway in transgenic plants is anticipated to cause complex interactions between phloem-feeding insects and their host plants due to predicted contradiction between two defense forces: the toxicity of various phenylpropanoids and the accumulation of SA via a branch of the activated pathway. METHODOLOGY/PRINCIPAL FINDINGS: Here, we investigated the effect of activating the phenylpropanoids pathway in Nicotiana tabacum, by over-expression of the PAP1 transcription factor, on the whitefly Bemisia tabaci, a phloem-feeding insect model. Our performance assays indicated that the over-expression made the transgenic plants a more suitable host for B. tabaci than wild-type (WT) plants, although these plants accumulated significantly higher levels of flavonoids. Transcription analyses of indicator genes in the SA (PR1a) and JA/ET (ERF1, COI1 and AOC) pathways followed by quantification of the SA and JA hormone levels, indicated that B. tabaci infestation periods longer than 8 hours, caused higher levels of activity of SA signaling in transgenic plants and higher levels of JA/ET signaling in WT plants. CONCLUSIONS/SIGNIFICANCE: Taken together, these results emphasize the important role JA/ET-induced defenses play in protecting plants from successful infestation by B. tabaci and likely other phloem-feeding insects. It also indicates the necessity of phloem feeders to suppress these defenses for efficient utilization of plant hosts. Our data also indicate that the defensive chemistry produced by the phenylpropanoids pathway has only a minor effect on the insect fitness" |
Keywords: | Animals Cyclopentanes/*metabolism Female Gene Expression Hemiptera/*physiology Herbivory Male *Metabolic Networks and Pathways Oxylipins/*metabolism Pancreatitis-Associated Proteins Plant Growth Regulators/*metabolism Plant Proteins/genetics/metabolism Pl; |
Notes: | "MedlineAlon, Michal Malka, Osnat Eakteiman, Galit Elbaz, Moshe Moyal Ben Zvi, Michal Vainstein, Alexander Morin, Shai eng Research Support, Non-U.S. Gov't 2013/11/10 PLoS One. 2013 Oct 25; 8(10):e76619. doi: 10.1371/journal.pone.0076619. eCollection 2013" |