Unknown,Transcriptomics,Genomics,Proteomics

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JHI At v4 RH timecourse

ABSTRACT: Salicylic acid (SA) and jasmonic acid (JA) fulfill key signaling functions in plant responses to herbivores. However, the mechanisms that facilitate systemic signaling in response to phloem-feeding insects remain poorly defined. Rapid local and systemic transcriptome reprogramming patterns observed in Arabidopsis thaliana following infestation by the green peach aphid (Myzus persicae Sulzer) identify abscisic acid (ABA) and redox-signalling as key factors in the transmission of signals from local to systemic leaves. Moreover, aphid fecundity was increased in mutants that were defective in ABA-signaling through ABA-INSENSITIVE 4 and show constitutive up-regulation of SA- and JA-mediated defense pathways. Conversely, aphid fecundity was decreased and aphid vigor was impaired on vitamin C2 mutants that are defective in the major low molecular weight antioxidant of plant cells, ascorbic acid and show constitutive up-regulation of redox defense and SA-mediated pathways but reduced up-regulation of JA-mediated pathways. Crossing vtc2 with abi4 restored the wild type sensitivity to aphids. Hence aphid fecundity was attenuated by low ascorbate in a manner that was dependent on the functions of the ABI4 transcription factor. ABI4 is not only an important regulator of systemic defenses against aphids but it makes a significant contribution to the SA-mediated repression of JA signaling.

ORGANISM(S): Arabidopsis thaliana

SUBMITTER: Pete Hedley

PROVIDER: E-MTAB-1140 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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